1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
|
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>
MySQL
—
SQLAlchemy 0.9 Documentation
</title>
<!-- begin iterate through SQLA + sphinx environment css_files -->
<link rel="stylesheet" href="../_static/pygments.css" type="text/css" />
<link rel="stylesheet" href="../_static/docs.css" type="text/css" />
<link rel="stylesheet" href="../_static/sphinx_paramlinks.css" type="text/css" />
<link rel="stylesheet" href="../_static/changelog.css" type="text/css" />
<!-- end iterate through SQLA + sphinx environment css_files -->
<!-- begin layout.mako headers -->
<script type="text/javascript">
var DOCUMENTATION_OPTIONS = {
URL_ROOT: '../',
VERSION: '0.9.8',
COLLAPSE_MODINDEX: false,
FILE_SUFFIX: '.html'
};
</script>
<!-- begin iterate through sphinx environment script_files -->
<script type="text/javascript" src="../_static/jquery.js"></script>
<script type="text/javascript" src="../_static/underscore.js"></script>
<script type="text/javascript" src="../_static/doctools.js"></script>
<!-- end iterate through sphinx environment script_files -->
<script type="text/javascript" src="../_static/detectmobile.js"></script>
<script type="text/javascript" src="../_static/init.js"></script>
<link rel="index" title="Index" href="../genindex.html" />
<link rel="search" title="Search" href="../search.html" />
<link rel="copyright" title="Copyright" href="../copyright.html" />
<link rel="top" title="SQLAlchemy 0.9 Documentation" href="../index.html" />
<link rel="up" title="Dialects" href="index.html" />
<link rel="next" title="Oracle" href="oracle.html" />
<link rel="prev" title="Microsoft SQL Server" href="mssql.html" />
<!-- end layout.mako headers -->
</head>
<body>
<div id="docs-container">
<div id="docs-top-navigation-container" class="body-background">
<div id="docs-header">
<div id="docs-version-header">
Release: <span class="version-num">0.9.8</span> | Release Date: October 13, 2014
</div>
<h1>SQLAlchemy 0.9 Documentation</h1>
</div>
</div>
<div id="docs-body-container">
<div id="fixed-sidebar" class="withsidebar">
<div id="docs-sidebar-popout">
<h3><a href="../index.html">SQLAlchemy 0.9 Documentation</a></h3>
<p id="sidebar-paginate">
<a href="index.html" title="Dialects">Up</a> |
<a href="mssql.html" title="Microsoft SQL Server">Prev</a> |
<a href="oracle.html" title="Oracle">Next</a>
</p>
<p id="sidebar-topnav">
<a href="../index.html">Contents</a> |
<a href="../genindex.html">Index</a>
</p>
<div id="sidebar-search">
<form class="search" action="../search.html" method="get">
<input type="text" name="q" size="12" /> <input type="submit" value="Search" />
<input type="hidden" name="check_keywords" value="yes" />
<input type="hidden" name="area" value="default" />
</form>
</div>
</div>
<div id="docs-sidebar">
<h3><a href="#">
MySQL
</a></h3>
<ul>
<li><a class="reference internal" href="#">MySQL</a><ul>
<li><a class="reference internal" href="#dialect-mysql">Support for the MySQL database.</a></li>
<li><a class="reference internal" href="#supported-versions-and-features">Supported Versions and Features</a></li>
<li><a class="reference internal" href="#connection-timeouts">Connection Timeouts</a></li>
<li><a class="reference internal" href="#create-table-arguments-including-storage-engines">CREATE TABLE arguments including Storage Engines</a></li>
<li><a class="reference internal" href="#case-sensitivity-and-table-reflection">Case Sensitivity and Table Reflection</a></li>
<li><a class="reference internal" href="#transaction-isolation-level">Transaction Isolation Level</a></li>
<li><a class="reference internal" href="#auto-increment-behavior">AUTO_INCREMENT Behavior</a></li>
<li><a class="reference internal" href="#ansi-quoting-style">Ansi Quoting Style</a></li>
<li><a class="reference internal" href="#mysql-sql-extensions">MySQL SQL Extensions</a></li>
<li><a class="reference internal" href="#rowcount-support">rowcount Support</a></li>
<li><a class="reference internal" href="#cast-support">CAST Support</a></li>
<li><a class="reference internal" href="#mysql-specific-index-options">MySQL Specific Index Options</a><ul>
<li><a class="reference internal" href="#index-length">Index Length</a></li>
<li><a class="reference internal" href="#index-types">Index Types</a></li>
</ul>
</li>
<li><a class="reference internal" href="#mysql-foreign-keys">MySQL Foreign Keys</a><ul>
<li><a class="reference internal" href="#foreign-key-arguments-to-avoid">Foreign Key Arguments to Avoid</a></li>
<li><a class="reference internal" href="#reflection-of-foreign-key-constraints">Reflection of Foreign Key Constraints</a></li>
</ul>
</li>
<li><a class="reference internal" href="#timestamp-columns-and-null">TIMESTAMP Columns and NULL</a></li>
<li><a class="reference internal" href="#mysql-data-types">MySQL Data Types</a></li>
<li><a class="reference internal" href="#module-sqlalchemy.dialects.mysql.mysqldb">MySQL-Python</a><ul>
<li><a class="reference internal" href="#dialect-mysql-mysqldb-url">DBAPI</a></li>
<li><a class="reference internal" href="#dialect-mysql-mysqldb-connect">Connecting</a></li>
<li><a class="reference internal" href="#unicode">Unicode</a></li>
<li><a class="reference internal" href="#known-issues">Known Issues</a></li>
</ul>
</li>
<li><a class="reference internal" href="#module-sqlalchemy.dialects.mysql.oursql">OurSQL</a><ul>
<li><a class="reference internal" href="#dialect-mysql-oursql-url">DBAPI</a></li>
<li><a class="reference internal" href="#dialect-mysql-oursql-connect">Connecting</a></li>
<li><a class="reference internal" href="#id2">Unicode</a></li>
</ul>
</li>
<li><a class="reference internal" href="#module-sqlalchemy.dialects.mysql.pymysql">pymysql</a><ul>
<li><a class="reference internal" href="#dialect-mysql-pymysql-url">DBAPI</a></li>
<li><a class="reference internal" href="#dialect-mysql-pymysql-connect">Connecting</a></li>
<li><a class="reference internal" href="#mysql-python-compatibility">MySQL-Python Compatibility</a></li>
</ul>
</li>
<li><a class="reference internal" href="#module-sqlalchemy.dialects.mysql.mysqlconnector">MySQL-Connector</a><ul>
<li><a class="reference internal" href="#dialect-mysql-mysqlconnector-url">DBAPI</a></li>
<li><a class="reference internal" href="#dialect-mysql-mysqlconnector-connect">Connecting</a></li>
</ul>
</li>
<li><a class="reference internal" href="#module-sqlalchemy.dialects.mysql.cymysql">cymysql</a><ul>
<li><a class="reference internal" href="#dialect-mysql-cymysql-url">DBAPI</a></li>
<li><a class="reference internal" href="#dialect-mysql-cymysql-connect">Connecting</a></li>
</ul>
</li>
<li><a class="reference internal" href="#module-sqlalchemy.dialects.mysql.gaerdbms">Google App Engine</a><ul>
<li><a class="reference internal" href="#dialect-mysql-gaerdbms-url">DBAPI</a></li>
<li><a class="reference internal" href="#dialect-mysql-gaerdbms-connect">Connecting</a></li>
<li><a class="reference internal" href="#pooling">Pooling</a></li>
</ul>
</li>
<li><a class="reference internal" href="#module-sqlalchemy.dialects.mysql.pyodbc">pyodbc</a><ul>
<li><a class="reference internal" href="#dialect-mysql-pyodbc-url">DBAPI</a></li>
<li><a class="reference internal" href="#dialect-mysql-pyodbc-connect">Connecting</a></li>
<li><a class="reference internal" href="#limitations">Limitations</a></li>
</ul>
</li>
<li><a class="reference internal" href="#module-sqlalchemy.dialects.mysql.zxjdbc">zxjdbc</a><ul>
<li><a class="reference internal" href="#dialect-mysql-zxjdbc-url">DBAPI</a></li>
<li><a class="reference internal" href="#dialect-mysql-zxjdbc-connect">Connecting</a></li>
<li><a class="reference internal" href="#character-sets">Character Sets</a></li>
</ul>
</li>
</ul>
</li>
</ul>
</div>
</div>
<div id="docs-body" class="withsidebar" >
<div class="section" id="module-sqlalchemy.dialects.mysql.base">
<span id="mysql"></span><span id="mysql-toplevel"></span><h1>MySQL<a class="headerlink" href="#module-sqlalchemy.dialects.mysql.base" title="Permalink to this headline">¶</a></h1>
<div class="section" id="dialect-mysql">
<p>Support for the MySQL database.</p>
<h2>DBAPI Support<a class="headerlink" href="#dialect-mysql" title="Permalink to this headline">¶</a></h2>
<p>The following dialect/DBAPI options are available. Please refer to individual DBAPI sections for connect information.<ul class="simple">
<li><a class="reference external" href="#module-sqlalchemy.dialects.mysql.mysqldb">MySQL-Python</a></li>
<li><a class="reference external" href="#module-sqlalchemy.dialects.mysql.oursql">OurSQL</a></li>
<li><a class="reference external" href="#module-sqlalchemy.dialects.mysql.pymysql">PyMySQL</a></li>
<li><a class="reference external" href="#module-sqlalchemy.dialects.mysql.mysqlconnector">MySQL Connector/Python</a></li>
<li><a class="reference external" href="#module-sqlalchemy.dialects.mysql.cymysql">CyMySQL</a></li>
<li><a class="reference external" href="#module-sqlalchemy.dialects.mysql.gaerdbms">Google Cloud SQL</a></li>
<li><a class="reference external" href="#module-sqlalchemy.dialects.mysql.pyodbc">PyODBC</a></li>
<li><a class="reference external" href="#module-sqlalchemy.dialects.mysql.zxjdbc">zxjdbc for Jython</a></li>
</ul>
</p>
</div>
<div class="section" id="supported-versions-and-features">
<h2>Supported Versions and Features<a class="headerlink" href="#supported-versions-and-features" title="Permalink to this headline">¶</a></h2>
<p>SQLAlchemy supports MySQL starting with version 4.1 through modern releases.
However, no heroic measures are taken to work around major missing
SQL features - if your server version does not support sub-selects, for
example, they won’t work in SQLAlchemy either.</p>
<p>See the official MySQL documentation for detailed information about features
supported in any given server release.</p>
</div>
<div class="section" id="connection-timeouts">
<span id="mysql-connection-timeouts"></span><h2>Connection Timeouts<a class="headerlink" href="#connection-timeouts" title="Permalink to this headline">¶</a></h2>
<p>MySQL features an automatic connection close behavior, for connections that
have been idle for eight hours or more. To circumvent having this issue, use
the <tt class="docutils literal"><span class="pre">pool_recycle</span></tt> option which controls the maximum age of any connection:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">engine</span> <span class="o">=</span> <span class="n">create_engine</span><span class="p">(</span><span class="s">'mysql+mysqldb://...'</span><span class="p">,</span> <span class="n">pool_recycle</span><span class="o">=</span><span class="mi">3600</span><span class="p">)</span></pre></div>
</div>
</div>
<div class="section" id="create-table-arguments-including-storage-engines">
<span id="mysql-storage-engines"></span><h2>CREATE TABLE arguments including Storage Engines<a class="headerlink" href="#create-table-arguments-including-storage-engines" title="Permalink to this headline">¶</a></h2>
<p>MySQL’s CREATE TABLE syntax includes a wide array of special options,
including <tt class="docutils literal"><span class="pre">ENGINE</span></tt>, <tt class="docutils literal"><span class="pre">CHARSET</span></tt>, <tt class="docutils literal"><span class="pre">MAX_ROWS</span></tt>, <tt class="docutils literal"><span class="pre">ROW_FORMAT</span></tt>,
<tt class="docutils literal"><span class="pre">INSERT_METHOD</span></tt>, and many more.
To accommodate the rendering of these arguments, specify the form
<tt class="docutils literal"><span class="pre">mysql_argument_name="value"</span></tt>. For example, to specify a table with
<tt class="docutils literal"><span class="pre">ENGINE</span></tt> of <tt class="docutils literal"><span class="pre">InnoDB</span></tt>, <tt class="docutils literal"><span class="pre">CHARSET</span></tt> of <tt class="docutils literal"><span class="pre">utf8</span></tt>, and <tt class="docutils literal"><span class="pre">KEY_BLOCK_SIZE</span></tt>
of <tt class="docutils literal"><span class="pre">1024</span></tt>:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">Table</span><span class="p">(</span><span class="s">'mytable'</span><span class="p">,</span> <span class="n">metadata</span><span class="p">,</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'data'</span><span class="p">,</span> <span class="n">String</span><span class="p">(</span><span class="mi">32</span><span class="p">)),</span>
<span class="n">mysql_engine</span><span class="o">=</span><span class="s">'InnoDB'</span><span class="p">,</span>
<span class="n">mysql_charset</span><span class="o">=</span><span class="s">'utf8'</span><span class="p">,</span>
<span class="n">mysql_key_block_size</span><span class="o">=</span><span class="s">"1024"</span>
<span class="p">)</span></pre></div>
</div>
<p>The MySQL dialect will normally transfer any keyword specified as
<tt class="docutils literal"><span class="pre">mysql_keyword_name</span></tt> to be rendered as <tt class="docutils literal"><span class="pre">KEYWORD_NAME</span></tt> in the
<tt class="docutils literal"><span class="pre">CREATE</span> <span class="pre">TABLE</span></tt> statement. A handful of these names will render with a space
instead of an underscore; to support this, the MySQL dialect has awareness of
these particular names, which include <tt class="docutils literal"><span class="pre">DATA</span> <span class="pre">DIRECTORY</span></tt>
(e.g. <tt class="docutils literal"><span class="pre">mysql_data_directory</span></tt>), <tt class="docutils literal"><span class="pre">CHARACTER</span> <span class="pre">SET</span></tt> (e.g.
<tt class="docutils literal"><span class="pre">mysql_character_set</span></tt>) and <tt class="docutils literal"><span class="pre">INDEX</span> <span class="pre">DIRECTORY</span></tt> (e.g.
<tt class="docutils literal"><span class="pre">mysql_index_directory</span></tt>).</p>
<p>The most common argument is <tt class="docutils literal"><span class="pre">mysql_engine</span></tt>, which refers to the storage
engine for the table. Historically, MySQL server installations would default
to <tt class="docutils literal"><span class="pre">MyISAM</span></tt> for this value, although newer versions may be defaulting
to <tt class="docutils literal"><span class="pre">InnoDB</span></tt>. The <tt class="docutils literal"><span class="pre">InnoDB</span></tt> engine is typically preferred for its support
of transactions and foreign keys.</p>
<p>A <a class="reference internal" href="../core/metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> that is created in a MySQL database with a storage engine
of <tt class="docutils literal"><span class="pre">MyISAM</span></tt> will be essentially non-transactional, meaning any
INSERT/UPDATE/DELETE statement referring to this table will be invoked as
autocommit. It also will have no support for foreign key constraints; while
the <tt class="docutils literal"><span class="pre">CREATE</span> <span class="pre">TABLE</span></tt> statement accepts foreign key options, when using the
<tt class="docutils literal"><span class="pre">MyISAM</span></tt> storage engine these arguments are discarded. Reflecting such a
table will also produce no foreign key constraint information.</p>
<p>For fully atomic transactions as well as support for foreign key
constraints, all participating <tt class="docutils literal"><span class="pre">CREATE</span> <span class="pre">TABLE</span></tt> statements must specify a
transactional engine, which in the vast majority of cases is <tt class="docutils literal"><span class="pre">InnoDB</span></tt>.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference external" href="http://dev.mysql.com/doc/refman/5.0/en/innodb-storage-engine.html">The InnoDB Storage Engine</a> -
on the MySQL website.</p>
</div>
</div>
<div class="section" id="case-sensitivity-and-table-reflection">
<h2>Case Sensitivity and Table Reflection<a class="headerlink" href="#case-sensitivity-and-table-reflection" title="Permalink to this headline">¶</a></h2>
<p>MySQL has inconsistent support for case-sensitive identifier
names, basing support on specific details of the underlying
operating system. However, it has been observed that no matter
what case sensitivity behavior is present, the names of tables in
foreign key declarations are <em>always</em> received from the database
as all-lower case, making it impossible to accurately reflect a
schema where inter-related tables use mixed-case identifier names.</p>
<p>Therefore it is strongly advised that table names be declared as
all lower case both within SQLAlchemy as well as on the MySQL
database itself, especially if database reflection features are
to be used.</p>
</div>
<div class="section" id="transaction-isolation-level">
<span id="mysql-isolation-level"></span><h2>Transaction Isolation Level<a class="headerlink" href="#transaction-isolation-level" title="Permalink to this headline">¶</a></h2>
<p><a class="reference internal" href="../core/engines.html#sqlalchemy.create_engine" title="sqlalchemy.create_engine"><tt class="xref py py-func docutils literal"><span class="pre">create_engine()</span></tt></a> accepts an <tt class="docutils literal"><span class="pre">isolation_level</span></tt>
parameter which results in the command <tt class="docutils literal"><span class="pre">SET</span> <span class="pre">SESSION</span>
<span class="pre">TRANSACTION</span> <span class="pre">ISOLATION</span> <span class="pre">LEVEL</span> <span class="pre"><level></span></tt> being invoked for
every new connection. Valid values for this parameter are
<tt class="docutils literal"><span class="pre">READ</span> <span class="pre">COMMITTED</span></tt>, <tt class="docutils literal"><span class="pre">READ</span> <span class="pre">UNCOMMITTED</span></tt>,
<tt class="docutils literal"><span class="pre">REPEATABLE</span> <span class="pre">READ</span></tt>, and <tt class="docutils literal"><span class="pre">SERIALIZABLE</span></tt>:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">engine</span> <span class="o">=</span> <span class="n">create_engine</span><span class="p">(</span>
<span class="s">"mysql://scott:tiger@localhost/test"</span><span class="p">,</span>
<span class="n">isolation_level</span><span class="o">=</span><span class="s">"READ UNCOMMITTED"</span>
<span class="p">)</span></pre></div>
</div>
<div class="versionadded">
<p><span>New in version 0.7.6.</span></p>
</div>
</div>
<div class="section" id="auto-increment-behavior">
<h2>AUTO_INCREMENT Behavior<a class="headerlink" href="#auto-increment-behavior" title="Permalink to this headline">¶</a></h2>
<p>When creating tables, SQLAlchemy will automatically set <tt class="docutils literal"><span class="pre">AUTO_INCREMENT</span></tt> on
the first <a class="reference internal" href="../core/types.html#sqlalchemy.types.Integer" title="sqlalchemy.types.Integer"><tt class="xref py py-class docutils literal"><span class="pre">Integer</span></tt></a> primary key column which is not marked as a
foreign key:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">t</span> <span class="o">=</span> <span class="n">Table</span><span class="p">(</span><span class="s">'mytable'</span><span class="p">,</span> <span class="n">metadata</span><span class="p">,</span>
<span class="gp">... </span> <span class="n">Column</span><span class="p">(</span><span class="s">'mytable_id'</span><span class="p">,</span> <span class="n">Integer</span><span class="p">,</span> <span class="n">primary_key</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span>
<span class="gp">... </span><span class="p">)</span>
<span class="gp">>>> </span><span class="n">t</span><span class="o">.</span><span class="n">create</span><span class="p">()</span>
<span class="go">CREATE TABLE mytable (</span>
<span class="go"> id INTEGER NOT NULL AUTO_INCREMENT,</span>
<span class="go"> PRIMARY KEY (id)</span>
<span class="go">)</span></pre></div>
</div>
<p>You can disable this behavior by passing <tt class="docutils literal"><span class="pre">False</span></tt> to the
<a class="reference internal" href="../core/metadata.html#sqlalchemy.schema.Column.params.autoincrement" title="sqlalchemy.schema.Column"><tt class="xref py py-paramref docutils literal"><span class="pre">autoincrement</span></tt></a> argument of <a class="reference internal" href="../core/metadata.html#sqlalchemy.schema.Column" title="sqlalchemy.schema.Column"><tt class="xref py py-class docutils literal"><span class="pre">Column</span></tt></a>. This flag
can also be used to enable auto-increment on a secondary column in a
multi-column key for some storage engines:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">Table</span><span class="p">(</span><span class="s">'mytable'</span><span class="p">,</span> <span class="n">metadata</span><span class="p">,</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'gid'</span><span class="p">,</span> <span class="n">Integer</span><span class="p">,</span> <span class="n">primary_key</span><span class="o">=</span><span class="bp">True</span><span class="p">,</span> <span class="n">autoincrement</span><span class="o">=</span><span class="bp">False</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'id'</span><span class="p">,</span> <span class="n">Integer</span><span class="p">,</span> <span class="n">primary_key</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span>
<span class="p">)</span></pre></div>
</div>
</div>
<div class="section" id="ansi-quoting-style">
<h2>Ansi Quoting Style<a class="headerlink" href="#ansi-quoting-style" title="Permalink to this headline">¶</a></h2>
<p>MySQL features two varieties of identifier “quoting style”, one using
backticks and the other using quotes, e.g. <tt class="docutils literal"><span class="pre">`some_identifier`</span></tt> vs.
<tt class="docutils literal"><span class="pre">"some_identifier"</span></tt>. All MySQL dialects detect which version
is in use by checking the value of <tt class="docutils literal"><span class="pre">sql_mode</span></tt> when a connection is first
established with a particular <a class="reference internal" href="../core/connections.html#sqlalchemy.engine.Engine" title="sqlalchemy.engine.Engine"><tt class="xref py py-class docutils literal"><span class="pre">Engine</span></tt></a>. This quoting style comes
into play when rendering table and column names as well as when reflecting
existing database structures. The detection is entirely automatic and
no special configuration is needed to use either quoting style.</p>
<div class="versionchanged">
<p><span>Changed in version 0.6: </span>detection of ANSI quoting style is entirely automatic,
there’s no longer any end-user <tt class="docutils literal"><span class="pre">create_engine()</span></tt> options in this regard.</p>
</div>
</div>
<div class="section" id="mysql-sql-extensions">
<h2>MySQL SQL Extensions<a class="headerlink" href="#mysql-sql-extensions" title="Permalink to this headline">¶</a></h2>
<p>Many of the MySQL SQL extensions are handled through SQLAlchemy’s generic
function and operator support:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">table</span><span class="o">.</span><span class="n">select</span><span class="p">(</span><span class="n">table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">password</span><span class="o">==</span><span class="n">func</span><span class="o">.</span><span class="n">md5</span><span class="p">(</span><span class="s">'plaintext'</span><span class="p">))</span>
<span class="n">table</span><span class="o">.</span><span class="n">select</span><span class="p">(</span><span class="n">table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">username</span><span class="o">.</span><span class="n">op</span><span class="p">(</span><span class="s">'regexp'</span><span class="p">)(</span><span class="s">'^[a-d]'</span><span class="p">))</span></pre></div>
</div>
<p>And of course any valid MySQL statement can be executed as a string as well.</p>
<p>Some limited direct support for MySQL extensions to SQL is currently
available.</p>
<ul>
<li><p class="first">SELECT pragma:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">select</span><span class="p">(</span><span class="o">...</span><span class="p">,</span> <span class="n">prefixes</span><span class="o">=</span><span class="p">[</span><span class="s">'HIGH_PRIORITY'</span><span class="p">,</span> <span class="s">'SQL_SMALL_RESULT'</span><span class="p">])</span></pre></div>
</div>
</li>
<li><p class="first">UPDATE with LIMIT:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">update</span><span class="p">(</span><span class="o">...</span><span class="p">,</span> <span class="n">mysql_limit</span><span class="o">=</span><span class="mi">10</span><span class="p">)</span></pre></div>
</div>
</li>
</ul>
</div>
<div class="section" id="rowcount-support">
<h2>rowcount Support<a class="headerlink" href="#rowcount-support" title="Permalink to this headline">¶</a></h2>
<p>SQLAlchemy standardizes the DBAPI <tt class="docutils literal"><span class="pre">cursor.rowcount</span></tt> attribute to be the
usual definition of “number of rows matched by an UPDATE or DELETE” statement.
This is in contradiction to the default setting on most MySQL DBAPI drivers,
which is “number of rows actually modified/deleted”. For this reason, the
SQLAlchemy MySQL dialects always add the <tt class="docutils literal"><span class="pre">constants.CLIENT.FOUND_ROWS</span></tt>
flag, or whatever is equivalent for the target dialect, upon connection.
This setting is currently hardcoded.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="../core/connections.html#sqlalchemy.engine.ResultProxy.rowcount" title="sqlalchemy.engine.ResultProxy.rowcount"><tt class="xref py py-attr docutils literal"><span class="pre">ResultProxy.rowcount</span></tt></a></p>
</div>
</div>
<div class="section" id="cast-support">
<h2>CAST Support<a class="headerlink" href="#cast-support" title="Permalink to this headline">¶</a></h2>
<p>MySQL documents the CAST operator as available in version 4.0.2. When using
the SQLAlchemy <a class="reference internal" href="../core/sqlelement.html#sqlalchemy.sql.expression.cast" title="sqlalchemy.sql.expression.cast"><tt class="xref py py-func docutils literal"><span class="pre">cast()</span></tt></a> function, SQLAlchemy
will not render the CAST token on MySQL before this version, based on server
version detection, instead rendering the internal expression directly.</p>
<p>CAST may still not be desirable on an early MySQL version post-4.0.2, as it
didn’t add all datatype support until 4.1.1. If your application falls into
this narrow area, the behavior of CAST can be controlled using the
<a class="reference internal" href="../core/compiler.html"><em>Custom SQL Constructs and Compilation Extension</em></a> system, as per the recipe below:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy.sql.expression</span> <span class="kn">import</span> <span class="n">Cast</span>
<span class="kn">from</span> <span class="nn">sqlalchemy.ext.compiler</span> <span class="kn">import</span> <span class="n">compiles</span>
<span class="nd">@compiles</span><span class="p">(</span><span class="n">Cast</span><span class="p">,</span> <span class="s">'mysql'</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">_check_mysql_version</span><span class="p">(</span><span class="n">element</span><span class="p">,</span> <span class="n">compiler</span><span class="p">,</span> <span class="o">**</span><span class="n">kw</span><span class="p">):</span>
<span class="k">if</span> <span class="n">compiler</span><span class="o">.</span><span class="n">dialect</span><span class="o">.</span><span class="n">server_version_info</span> <span class="o"><</span> <span class="p">(</span><span class="mi">4</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">0</span><span class="p">):</span>
<span class="k">return</span> <span class="n">compiler</span><span class="o">.</span><span class="n">process</span><span class="p">(</span><span class="n">element</span><span class="o">.</span><span class="n">clause</span><span class="p">,</span> <span class="o">**</span><span class="n">kw</span><span class="p">)</span>
<span class="k">else</span><span class="p">:</span>
<span class="k">return</span> <span class="n">compiler</span><span class="o">.</span><span class="n">visit_cast</span><span class="p">(</span><span class="n">element</span><span class="p">,</span> <span class="o">**</span><span class="n">kw</span><span class="p">)</span></pre></div>
</div>
<p>The above function, which only needs to be declared once
within an application, overrides the compilation of the
<a class="reference internal" href="../core/sqlelement.html#sqlalchemy.sql.expression.cast" title="sqlalchemy.sql.expression.cast"><tt class="xref py py-func docutils literal"><span class="pre">cast()</span></tt></a> construct to check for version 4.1.0 before
fully rendering CAST; else the internal element of the
construct is rendered directly.</p>
</div>
<div class="section" id="mysql-specific-index-options">
<span id="mysql-indexes"></span><h2>MySQL Specific Index Options<a class="headerlink" href="#mysql-specific-index-options" title="Permalink to this headline">¶</a></h2>
<p>MySQL-specific extensions to the <a class="reference internal" href="../core/constraints.html#sqlalchemy.schema.Index" title="sqlalchemy.schema.Index"><tt class="xref py py-class docutils literal"><span class="pre">Index</span></tt></a> construct are available.</p>
<div class="section" id="index-length">
<h3>Index Length<a class="headerlink" href="#index-length" title="Permalink to this headline">¶</a></h3>
<p>MySQL provides an option to create index entries with a certain length, where
“length” refers to the number of characters or bytes in each value which will
become part of the index. SQLAlchemy provides this feature via the
<tt class="docutils literal"><span class="pre">mysql_length</span></tt> parameter:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">Index</span><span class="p">(</span><span class="s">'my_index'</span><span class="p">,</span> <span class="n">my_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">data</span><span class="p">,</span> <span class="n">mysql_length</span><span class="o">=</span><span class="mi">10</span><span class="p">)</span>
<span class="n">Index</span><span class="p">(</span><span class="s">'a_b_idx'</span><span class="p">,</span> <span class="n">my_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">a</span><span class="p">,</span> <span class="n">my_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">b</span><span class="p">,</span> <span class="n">mysql_length</span><span class="o">=</span><span class="p">{</span><span class="s">'a'</span><span class="p">:</span> <span class="mi">4</span><span class="p">,</span>
<span class="s">'b'</span><span class="p">:</span> <span class="mi">9</span><span class="p">})</span></pre></div>
</div>
<p>Prefix lengths are given in characters for nonbinary string types and in bytes
for binary string types. The value passed to the keyword argument <em>must</em> be
either an integer (and, thus, specify the same prefix length value for all
columns of the index) or a dict in which keys are column names and values are
prefix length values for corresponding columns. MySQL only allows a length for
a column of an index if it is for a CHAR, VARCHAR, TEXT, BINARY, VARBINARY and
BLOB.</p>
<div class="versionadded">
<p><span>New in version 0.8.2: </span><tt class="docutils literal"><span class="pre">mysql_length</span></tt> may now be specified as a dictionary
for use with composite indexes.</p>
</div>
</div>
<div class="section" id="index-types">
<h3>Index Types<a class="headerlink" href="#index-types" title="Permalink to this headline">¶</a></h3>
<p>Some MySQL storage engines permit you to specify an index type when creating
an index or primary key constraint. SQLAlchemy provides this feature via the
<tt class="docutils literal"><span class="pre">mysql_using</span></tt> parameter on <a class="reference internal" href="../core/constraints.html#sqlalchemy.schema.Index" title="sqlalchemy.schema.Index"><tt class="xref py py-class docutils literal"><span class="pre">Index</span></tt></a>:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">Index</span><span class="p">(</span><span class="s">'my_index'</span><span class="p">,</span> <span class="n">my_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">data</span><span class="p">,</span> <span class="n">mysql_using</span><span class="o">=</span><span class="s">'hash'</span><span class="p">)</span></pre></div>
</div>
<p>As well as the <tt class="docutils literal"><span class="pre">mysql_using</span></tt> parameter on <a class="reference internal" href="../core/constraints.html#sqlalchemy.schema.PrimaryKeyConstraint" title="sqlalchemy.schema.PrimaryKeyConstraint"><tt class="xref py py-class docutils literal"><span class="pre">PrimaryKeyConstraint</span></tt></a>:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">PrimaryKeyConstraint</span><span class="p">(</span><span class="s">"data"</span><span class="p">,</span> <span class="n">mysql_using</span><span class="o">=</span><span class="s">'hash'</span><span class="p">)</span></pre></div>
</div>
<p>The value passed to the keyword argument will be simply passed through to the
underlying CREATE INDEX or PRIMARY KEY clause, so it <em>must</em> be a valid index
type for your MySQL storage engine.</p>
<p>More information can be found at:</p>
<p><a class="reference external" href="http://dev.mysql.com/doc/refman/5.0/en/create-index.html">http://dev.mysql.com/doc/refman/5.0/en/create-index.html</a></p>
<p><a class="reference external" href="http://dev.mysql.com/doc/refman/5.0/en/create-table.html">http://dev.mysql.com/doc/refman/5.0/en/create-table.html</a></p>
</div>
</div>
<div class="section" id="mysql-foreign-keys">
<span id="id1"></span><h2>MySQL Foreign Keys<a class="headerlink" href="#mysql-foreign-keys" title="Permalink to this headline">¶</a></h2>
<p>MySQL’s behavior regarding foreign keys has some important caveats.</p>
<div class="section" id="foreign-key-arguments-to-avoid">
<h3>Foreign Key Arguments to Avoid<a class="headerlink" href="#foreign-key-arguments-to-avoid" title="Permalink to this headline">¶</a></h3>
<p>MySQL does not support the foreign key arguments “DEFERRABLE”, “INITIALLY”,
or “MATCH”. Using the <tt class="docutils literal"><span class="pre">deferrable</span></tt> or <tt class="docutils literal"><span class="pre">initially</span></tt> keyword argument with
<a class="reference internal" href="../core/constraints.html#sqlalchemy.schema.ForeignKeyConstraint" title="sqlalchemy.schema.ForeignKeyConstraint"><tt class="xref py py-class docutils literal"><span class="pre">ForeignKeyConstraint</span></tt></a> or <a class="reference internal" href="../core/constraints.html#sqlalchemy.schema.ForeignKey" title="sqlalchemy.schema.ForeignKey"><tt class="xref py py-class docutils literal"><span class="pre">ForeignKey</span></tt></a> will have the effect of
these keywords being rendered in a DDL expression, which will then raise an
error on MySQL. In order to use these keywords on a foreign key while having
them ignored on a MySQL backend, use a custom compile rule:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy.ext.compiler</span> <span class="kn">import</span> <span class="n">compiles</span>
<span class="kn">from</span> <span class="nn">sqlalchemy.schema</span> <span class="kn">import</span> <span class="n">ForeignKeyConstraint</span>
<span class="nd">@compiles</span><span class="p">(</span><span class="n">ForeignKeyConstraint</span><span class="p">,</span> <span class="s">"mysql"</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">process</span><span class="p">(</span><span class="n">element</span><span class="p">,</span> <span class="n">compiler</span><span class="p">,</span> <span class="o">**</span><span class="n">kw</span><span class="p">):</span>
<span class="n">element</span><span class="o">.</span><span class="n">deferrable</span> <span class="o">=</span> <span class="n">element</span><span class="o">.</span><span class="n">initially</span> <span class="o">=</span> <span class="bp">None</span>
<span class="k">return</span> <span class="n">compiler</span><span class="o">.</span><span class="n">visit_foreign_key_constraint</span><span class="p">(</span><span class="n">element</span><span class="p">,</span> <span class="o">**</span><span class="n">kw</span><span class="p">)</span></pre></div>
</div>
<div class="versionchanged">
<p><span>Changed in version 0.9.0: </span>- the MySQL backend no longer silently ignores
the <tt class="docutils literal"><span class="pre">deferrable</span></tt> or <tt class="docutils literal"><span class="pre">initially</span></tt> keyword arguments of
<a class="reference internal" href="../core/constraints.html#sqlalchemy.schema.ForeignKeyConstraint" title="sqlalchemy.schema.ForeignKeyConstraint"><tt class="xref py py-class docutils literal"><span class="pre">ForeignKeyConstraint</span></tt></a> and <a class="reference internal" href="../core/constraints.html#sqlalchemy.schema.ForeignKey" title="sqlalchemy.schema.ForeignKey"><tt class="xref py py-class docutils literal"><span class="pre">ForeignKey</span></tt></a>.</p>
</div>
<p>The “MATCH” keyword is in fact more insidious, and is explicitly disallowed
by SQLAlchemy in conjunction with the MySQL backend. This argument is
silently ignored by MySQL, but in addition has the effect of ON UPDATE and ON
DELETE options also being ignored by the backend. Therefore MATCH should
never be used with the MySQL backend; as is the case with DEFERRABLE and
INITIALLY, custom compilation rules can be used to correct a MySQL
ForeignKeyConstraint at DDL definition time.</p>
<div class="versionadded">
<p><span>New in version 0.9.0: </span>- the MySQL backend will raise a
<tt class="xref py py-class docutils literal"><span class="pre">CompileError</span></tt> when the <tt class="docutils literal"><span class="pre">match</span></tt> keyword is used with
<a class="reference internal" href="../core/constraints.html#sqlalchemy.schema.ForeignKeyConstraint" title="sqlalchemy.schema.ForeignKeyConstraint"><tt class="xref py py-class docutils literal"><span class="pre">ForeignKeyConstraint</span></tt></a> or <a class="reference internal" href="../core/constraints.html#sqlalchemy.schema.ForeignKey" title="sqlalchemy.schema.ForeignKey"><tt class="xref py py-class docutils literal"><span class="pre">ForeignKey</span></tt></a>.</p>
</div>
</div>
<div class="section" id="reflection-of-foreign-key-constraints">
<h3>Reflection of Foreign Key Constraints<a class="headerlink" href="#reflection-of-foreign-key-constraints" title="Permalink to this headline">¶</a></h3>
<p>Not all MySQL storage engines support foreign keys. When using the
very common <tt class="docutils literal"><span class="pre">MyISAM</span></tt> MySQL storage engine, the information loaded by table
reflection will not include foreign keys. For these tables, you may supply a
<tt class="xref py py-class docutils literal"><span class="pre">ForeignKeyConstraint</span></tt> at reflection time:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">Table</span><span class="p">(</span><span class="s">'mytable'</span><span class="p">,</span> <span class="n">metadata</span><span class="p">,</span>
<span class="n">ForeignKeyConstraint</span><span class="p">([</span><span class="s">'other_id'</span><span class="p">],</span> <span class="p">[</span><span class="s">'othertable.other_id'</span><span class="p">]),</span>
<span class="n">autoload</span><span class="o">=</span><span class="bp">True</span>
<span class="p">)</span></pre></div>
</div>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#mysql-storage-engines"><em>CREATE TABLE arguments including Storage Engines</em></a></p>
</div>
</div>
</div>
<div class="section" id="timestamp-columns-and-null">
<span id="mysql-timestamp-null"></span><h2>TIMESTAMP Columns and NULL<a class="headerlink" href="#timestamp-columns-and-null" title="Permalink to this headline">¶</a></h2>
<p>MySQL enforces that a column which specifies the TIMESTAMP datatype implicitly
includes a default value of CURRENT_TIMESTAMP, even though this is not
stated, and additionally sets the column as NOT NULL, the opposite behavior
vs. that of all other datatypes:</p>
<div class="highlight-python"><pre>mysql> CREATE TABLE ts_test (
-> a INTEGER,
-> b INTEGER NOT NULL,
-> c TIMESTAMP,
-> d TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
-> e TIMESTAMP NULL);
Query OK, 0 rows affected (0.03 sec)
mysql> SHOW CREATE TABLE ts_test;
+---------+-----------------------------------------------------
| Table | Create Table
+---------+-----------------------------------------------------
| ts_test | CREATE TABLE `ts_test` (
`a` int(11) DEFAULT NULL,
`b` int(11) NOT NULL,
`c` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
`d` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP,
`e` timestamp NULL DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1</pre>
</div>
<p>Above, we see that an INTEGER column defaults to NULL, unless it is specified
with NOT NULL. But when the column is of type TIMESTAMP, an implicit
default of CURRENT_TIMESTAMP is generated which also coerces the column
to be a NOT NULL, even though we did not specify it as such.</p>
<p>Therefore, the usual “NOT NULL” clause <em>does not apply</em> to a TIMESTAMP
column; MySQL selects this implicitly. SQLAlchemy therefore does not render
NOT NULL for a TIMESTAMP column on MySQL. However, it <em>does</em> render
NULL when we specify nullable=True, or if we leave nullable absent, as it
also defaults to True. This is to accommodate the essentially
reverse behavior of the NULL flag for TIMESTAMP:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">MetaData</span><span class="p">,</span> <span class="n">TIMESTAMP</span><span class="p">,</span> <span class="n">Integer</span><span class="p">,</span> <span class="n">Table</span><span class="p">,</span> <span class="n">Column</span><span class="p">,</span> <span class="n">text</span>
<span class="n">m</span> <span class="o">=</span> <span class="n">MetaData</span><span class="p">()</span>
<span class="n">t</span> <span class="o">=</span> <span class="n">Table</span><span class="p">(</span><span class="s">'ts_test'</span><span class="p">,</span> <span class="n">m</span><span class="p">,</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'a'</span><span class="p">,</span> <span class="n">Integer</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'b'</span><span class="p">,</span> <span class="n">Integer</span><span class="p">,</span> <span class="n">nullable</span><span class="o">=</span><span class="bp">False</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'c'</span><span class="p">,</span> <span class="n">TIMESTAMP</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'d'</span><span class="p">,</span> <span class="n">TIMESTAMP</span><span class="p">,</span> <span class="n">nullable</span><span class="o">=</span><span class="bp">False</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'e'</span><span class="p">,</span> <span class="n">TIMESTAMP</span><span class="p">,</span> <span class="n">nullable</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span>
<span class="p">)</span>
<span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">create_engine</span>
<span class="n">e</span> <span class="o">=</span> <span class="n">create_engine</span><span class="p">(</span><span class="s">"mysql://scott:tiger@localhost/test"</span><span class="p">,</span> <span class="n">echo</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span>
<span class="n">m</span><span class="o">.</span><span class="n">create_all</span><span class="p">(</span><span class="n">e</span><span class="p">)</span></pre></div>
</div>
<p>In the output, we can see that the TIMESTAMP column receives a different
treatment for NULL / NOT NULL vs. that of the INTEGER:</p>
<div class="highlight-python"><pre>CREATE TABLE ts_test (
a INTEGER,
b INTEGER NOT NULL,
c TIMESTAMP NULL,
d TIMESTAMP,
e TIMESTAMP NULL
)</pre>
</div>
<p>MySQL above receives the NULL/NOT NULL constraint as is stated in our
original <a class="reference internal" href="../core/metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a>:</p>
<div class="highlight-python"><pre>mysql> SHOW CREATE TABLE ts_test;
+---------+---------------------------
| Table | Create Table
+---------+---------------------------
| ts_test | CREATE TABLE `ts_test` (
`a` int(11) DEFAULT NULL,
`b` int(11) NOT NULL,
`c` timestamp NULL DEFAULT NULL,
`d` timestamp NOT NULL DEFAULT '0000-00-00 00:00:00',
`e` timestamp NULL DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1</pre>
</div>
<p>Be sure to always favor the <tt class="docutils literal"><span class="pre">SHOW</span> <span class="pre">CREATE</span> <span class="pre">TABLE</span></tt> output over the
SQLAlchemy-emitted DDL when checking table definitions, as MySQL’s
rules can be hard to predict.</p>
</div>
<div class="section" id="mysql-data-types">
<h2>MySQL Data Types<a class="headerlink" href="#mysql-data-types" title="Permalink to this headline">¶</a></h2>
<p>As with all SQLAlchemy dialects, all UPPERCASE types that are known to be
valid with MySQL are importable from the top level dialect:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy.dialects.mysql</span> <span class="kn">import</span> \
<span class="n">BIGINT</span><span class="p">,</span> <span class="n">BINARY</span><span class="p">,</span> <span class="n">BIT</span><span class="p">,</span> <span class="n">BLOB</span><span class="p">,</span> <span class="n">BOOLEAN</span><span class="p">,</span> <span class="n">CHAR</span><span class="p">,</span> <span class="n">DATE</span><span class="p">,</span> \
<span class="n">DATETIME</span><span class="p">,</span> <span class="n">DECIMAL</span><span class="p">,</span> <span class="n">DECIMAL</span><span class="p">,</span> <span class="n">DOUBLE</span><span class="p">,</span> <span class="n">ENUM</span><span class="p">,</span> <span class="n">FLOAT</span><span class="p">,</span> <span class="n">INTEGER</span><span class="p">,</span> \
<span class="n">LONGBLOB</span><span class="p">,</span> <span class="n">LONGTEXT</span><span class="p">,</span> <span class="n">MEDIUMBLOB</span><span class="p">,</span> <span class="n">MEDIUMINT</span><span class="p">,</span> <span class="n">MEDIUMTEXT</span><span class="p">,</span> <span class="n">NCHAR</span><span class="p">,</span> \
<span class="n">NUMERIC</span><span class="p">,</span> <span class="n">NVARCHAR</span><span class="p">,</span> <span class="n">REAL</span><span class="p">,</span> <span class="n">SET</span><span class="p">,</span> <span class="n">SMALLINT</span><span class="p">,</span> <span class="n">TEXT</span><span class="p">,</span> <span class="n">TIME</span><span class="p">,</span> <span class="n">TIMESTAMP</span><span class="p">,</span> \
<span class="n">TINYBLOB</span><span class="p">,</span> <span class="n">TINYINT</span><span class="p">,</span> <span class="n">TINYTEXT</span><span class="p">,</span> <span class="n">VARBINARY</span><span class="p">,</span> <span class="n">VARCHAR</span><span class="p">,</span> <span class="n">YEAR</span></pre></div>
</div>
<p>Types which are specific to MySQL, or have MySQL-specific
construction arguments, are as follows:</p>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.BIGINT">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">BIGINT</tt><big>(</big><em>display_width=None</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.BIGINT" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.dialects.mysql.base._IntegerType</span></tt>, <a class="reference internal" href="../core/types.html#sqlalchemy.types.BIGINT" title="sqlalchemy.types.BIGINT"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types.BIGINT</span></tt></a></p>
<p>MySQL BIGINTEGER type.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.BIGINT.__init__">
<tt class="descname">__init__</tt><big>(</big><em>display_width=None</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.BIGINT.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a BIGINTEGER.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.BIGINT.params.display_width"></span><strong>display_width</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.BIGINT.params.display_width">¶</a> – Optional, maximum display width for this number.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.BIGINT.params.unsigned"></span><strong>unsigned</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.BIGINT.params.unsigned">¶</a> – a boolean, optional.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.BIGINT.params.zerofill"></span><strong>zerofill</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.BIGINT.params.zerofill">¶</a> – Optional. If true, values will be stored as strings
left-padded with zeros. Note that this does not effect the values
returned by the underlying database API, which continue to be
numeric.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.BINARY">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">BINARY</tt><big>(</big><em>length=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.BINARY" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types._Binary</span></tt></p>
<p>The SQL BINARY type.</p>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.BIT">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">BIT</tt><big>(</big><em>length=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.BIT" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <a class="reference internal" href="../core/types.html#sqlalchemy.types.TypeEngine" title="sqlalchemy.types.TypeEngine"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types.TypeEngine</span></tt></a></p>
<p>MySQL BIT type.</p>
<p>This type is for MySQL 5.0.3 or greater for MyISAM, and 5.0.5 or greater
for MyISAM, MEMORY, InnoDB and BDB. For older versions, use a
MSTinyInteger() type.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.BIT.__init__">
<tt class="descname">__init__</tt><big>(</big><em>length=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.BIT.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a BIT.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><span class="target" id="sqlalchemy.dialects.mysql.BIT.params.length"></span><strong>length</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.BIT.params.length">¶</a> – Optional, number of bits.</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.BLOB">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">BLOB</tt><big>(</big><em>length=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.BLOB" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <a class="reference internal" href="../core/types.html#sqlalchemy.types.LargeBinary" title="sqlalchemy.types.LargeBinary"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types.LargeBinary</span></tt></a></p>
<p>The SQL BLOB type.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.BLOB.__init__">
<tt class="descname">__init__</tt><big>(</big><em>length=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.BLOB.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a LargeBinary type.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><span class="target" id="sqlalchemy.dialects.mysql.BLOB.params.length"></span><strong>length</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.BLOB.params.length">¶</a> – optional, a length for the column for use in
DDL statements, for those BLOB types that accept a length
(i.e. MySQL). It does <em>not</em> produce a small BINARY/VARBINARY
type - use the BINARY/VARBINARY types specifically for those.
May be safely omitted if no <tt class="docutils literal"><span class="pre">CREATE</span>
<span class="pre">TABLE</span></tt> will be issued. Certain databases may require a
<em>length</em> for use in DDL, and will raise an exception when
the <tt class="docutils literal"><span class="pre">CREATE</span> <span class="pre">TABLE</span></tt> DDL is issued.</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.BOOLEAN">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">BOOLEAN</tt><big>(</big><em>create_constraint=True</em>, <em>name=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.BOOLEAN" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <a class="reference internal" href="../core/types.html#sqlalchemy.types.Boolean" title="sqlalchemy.types.Boolean"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types.Boolean</span></tt></a></p>
<p>The SQL BOOLEAN type.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.BOOLEAN.__init__">
<tt class="descname">__init__</tt><big>(</big><em>create_constraint=True</em>, <em>name=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.BOOLEAN.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a Boolean.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.BOOLEAN.params.create_constraint"></span><strong>create_constraint</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.BOOLEAN.params.create_constraint">¶</a> – defaults to True. If the boolean
is generated as an int/smallint, also create a CHECK constraint
on the table that ensures 1 or 0 as a value.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.BOOLEAN.params.name"></span><strong>name</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.BOOLEAN.params.name">¶</a> – if a CHECK constraint is generated, specify
the name of the constraint.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.CHAR">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">CHAR</tt><big>(</big><em>length=None</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.CHAR" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.dialects.mysql.base._StringType</span></tt>, <a class="reference internal" href="../core/types.html#sqlalchemy.types.CHAR" title="sqlalchemy.types.CHAR"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types.CHAR</span></tt></a></p>
<p>MySQL CHAR type, for fixed-length character data.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.CHAR.__init__">
<tt class="descname">__init__</tt><big>(</big><em>length=None</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.CHAR.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a CHAR.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.CHAR.params.length"></span><strong>length</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.CHAR.params.length">¶</a> – Maximum data length, in characters.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.CHAR.params.binary"></span><strong>binary</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.CHAR.params.binary">¶</a> – Optional, use the default binary collation for the
national character set. This does not affect the type of data
stored, use a BINARY type for binary data.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.CHAR.params.collation"></span><strong>collation</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.CHAR.params.collation">¶</a> – Optional, request a particular collation. Must be
compatible with the national character set.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.DATE">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">DATE</tt><a class="headerlink" href="#sqlalchemy.dialects.mysql.DATE" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <a class="reference internal" href="../core/types.html#sqlalchemy.types.Date" title="sqlalchemy.types.Date"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types.Date</span></tt></a></p>
<p>The SQL DATE type.</p>
<dl class="attribute">
<dt id="sqlalchemy.dialects.mysql.DATE.__init__">
<tt class="descname">__init__</tt><a class="headerlink" href="#sqlalchemy.dialects.mysql.DATE.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>x.__init__(...) initializes x; see help(type(x)) for signature</p>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.DATETIME">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">DATETIME</tt><big>(</big><em>timezone=False</em>, <em>fsp=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.DATETIME" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <a class="reference internal" href="../core/types.html#sqlalchemy.types.DATETIME" title="sqlalchemy.types.DATETIME"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types.DATETIME</span></tt></a></p>
<p>MySQL DATETIME type.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.DATETIME.__init__">
<tt class="descname">__init__</tt><big>(</big><em>timezone=False</em>, <em>fsp=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.DATETIME.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a MySQL DATETIME type.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.DATETIME.params.timezone"></span><strong>timezone</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.DATETIME.params.timezone">¶</a> – not used by the MySQL dialect.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.DATETIME.params.fsp"></span><strong>fsp</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.DATETIME.params.fsp">¶</a> – <p>fractional seconds precision value.
MySQL 5.6.4 supports storage of fractional seconds;
this parameter will be used when emitting DDL
for the DATETIME type.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">DBAPI driver support for fractional seconds may
be limited; current support includes
MySQL Connector/Python.</p>
</div>
</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="versionadded">
<p><span>New in version 0.8.5: </span>Added MySQL-specific <a class="reference internal" href="#sqlalchemy.dialects.mysql.DATETIME" title="sqlalchemy.dialects.mysql.DATETIME"><tt class="xref py py-class docutils literal"><span class="pre">mysql.DATETIME</span></tt></a>
with fractional seconds support.</p>
</div>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.DECIMAL">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">DECIMAL</tt><big>(</big><em>precision=None</em>, <em>scale=None</em>, <em>asdecimal=True</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.DECIMAL" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.dialects.mysql.base._NumericType</span></tt>, <a class="reference internal" href="../core/types.html#sqlalchemy.types.DECIMAL" title="sqlalchemy.types.DECIMAL"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types.DECIMAL</span></tt></a></p>
<p>MySQL DECIMAL type.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.DECIMAL.__init__">
<tt class="descname">__init__</tt><big>(</big><em>precision=None</em>, <em>scale=None</em>, <em>asdecimal=True</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.DECIMAL.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a DECIMAL.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.DECIMAL.params.precision"></span><strong>precision</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.DECIMAL.params.precision">¶</a> – Total digits in this number. If scale and precision
are both None, values are stored to limits allowed by the server.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.DECIMAL.params.scale"></span><strong>scale</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.DECIMAL.params.scale">¶</a> – The number of digits after the decimal point.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.DECIMAL.params.unsigned"></span><strong>unsigned</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.DECIMAL.params.unsigned">¶</a> – a boolean, optional.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.DECIMAL.params.zerofill"></span><strong>zerofill</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.DECIMAL.params.zerofill">¶</a> – Optional. If true, values will be stored as strings
left-padded with zeros. Note that this does not effect the values
returned by the underlying database API, which continue to be
numeric.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.DOUBLE">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">DOUBLE</tt><big>(</big><em>precision=None</em>, <em>scale=None</em>, <em>asdecimal=True</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.DOUBLE" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.dialects.mysql.base._FloatType</span></tt></p>
<p>MySQL DOUBLE type.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.DOUBLE.__init__">
<tt class="descname">__init__</tt><big>(</big><em>precision=None</em>, <em>scale=None</em>, <em>asdecimal=True</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.DOUBLE.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a DOUBLE.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">The <a class="reference internal" href="#sqlalchemy.dialects.mysql.DOUBLE" title="sqlalchemy.dialects.mysql.DOUBLE"><tt class="xref py py-class docutils literal"><span class="pre">DOUBLE</span></tt></a> type by default converts from float
to Decimal, using a truncation that defaults to 10 digits.
Specify either <tt class="docutils literal"><span class="pre">scale=n</span></tt> or <tt class="docutils literal"><span class="pre">decimal_return_scale=n</span></tt> in order
to change this scale, or <tt class="docutils literal"><span class="pre">asdecimal=False</span></tt> to return values
directly as Python floating points.</p>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.DOUBLE.params.precision"></span><strong>precision</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.DOUBLE.params.precision">¶</a> – Total digits in this number. If scale and precision
are both None, values are stored to limits allowed by the server.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.DOUBLE.params.scale"></span><strong>scale</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.DOUBLE.params.scale">¶</a> – The number of digits after the decimal point.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.DOUBLE.params.unsigned"></span><strong>unsigned</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.DOUBLE.params.unsigned">¶</a> – a boolean, optional.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.DOUBLE.params.zerofill"></span><strong>zerofill</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.DOUBLE.params.zerofill">¶</a> – Optional. If true, values will be stored as strings
left-padded with zeros. Note that this does not effect the values
returned by the underlying database API, which continue to be
numeric.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.ENUM">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">ENUM</tt><big>(</big><em>*enums</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.ENUM" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <a class="reference internal" href="../core/types.html#sqlalchemy.types.Enum" title="sqlalchemy.types.Enum"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types.Enum</span></tt></a>, <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.dialects.mysql.base._EnumeratedValues</span></tt></p>
<p>MySQL ENUM type.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.ENUM.__init__">
<tt class="descname">__init__</tt><big>(</big><em>*enums</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.ENUM.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct an ENUM.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">Column</span><span class="p">(</span><span class="s">'myenum'</span><span class="p">,</span> <span class="n">ENUM</span><span class="p">(</span><span class="s">"foo"</span><span class="p">,</span> <span class="s">"bar"</span><span class="p">,</span> <span class="s">"baz"</span><span class="p">))</span></pre></div>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.ENUM.params.enums"></span><strong>enums</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.ENUM.params.enums">¶</a> – The range of valid values for this ENUM. Values will be
quoted when generating the schema according to the quoting flag (see
below).</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.ENUM.params.strict"></span><strong>strict</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.ENUM.params.strict">¶</a> – Defaults to False: ensure that a given value is in this
ENUM’s range of permissible values when inserting or updating rows.
Note that MySQL will not raise a fatal error if you attempt to store
an out of range value- an alternate value will be stored instead.
(See MySQL ENUM documentation.)</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.ENUM.params.charset"></span><strong>charset</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.ENUM.params.charset">¶</a> – Optional, a column-level character set for this string
value. Takes precedence to ‘ascii’ or ‘unicode’ short-hand.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.ENUM.params.collation"></span><strong>collation</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.ENUM.params.collation">¶</a> – Optional, a column-level collation for this string
value. Takes precedence to ‘binary’ short-hand.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.ENUM.params.ascii"></span><strong>ascii</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.ENUM.params.ascii">¶</a> – Defaults to False: short-hand for the <tt class="docutils literal"><span class="pre">latin1</span></tt>
character set, generates ASCII in schema.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.ENUM.params.unicode"></span><strong>unicode</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.ENUM.params.unicode">¶</a> – Defaults to False: short-hand for the <tt class="docutils literal"><span class="pre">ucs2</span></tt>
character set, generates UNICODE in schema.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.ENUM.params.binary"></span><strong>binary</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.ENUM.params.binary">¶</a> – Defaults to False: short-hand, pick the binary
collation type that matches the column’s character set. Generates
BINARY in schema. This does not affect the type of data stored,
only the collation of character data.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.ENUM.params.quoting"></span><strong>quoting</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.ENUM.params.quoting">¶</a> – <p>Defaults to ‘auto’: automatically determine enum value
quoting. If all enum values are surrounded by the same quoting
character, then use ‘quoted’ mode. Otherwise, use ‘unquoted’ mode.</p>
<p>‘quoted’: values in enums are already quoted, they will be used
directly when generating the schema - this usage is deprecated.</p>
<p>‘unquoted’: values in enums are not quoted, they will be escaped and
surrounded by single quotes when generating the schema.</p>
<p>Previous versions of this type always required manually quoted
values to be supplied; future versions will always quote the string
literals for you. This is a transitional option.</p>
</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.FLOAT">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">FLOAT</tt><big>(</big><em>precision=None</em>, <em>scale=None</em>, <em>asdecimal=False</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.FLOAT" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.dialects.mysql.base._FloatType</span></tt>, <a class="reference internal" href="../core/types.html#sqlalchemy.types.FLOAT" title="sqlalchemy.types.FLOAT"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types.FLOAT</span></tt></a></p>
<p>MySQL FLOAT type.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.FLOAT.__init__">
<tt class="descname">__init__</tt><big>(</big><em>precision=None</em>, <em>scale=None</em>, <em>asdecimal=False</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.FLOAT.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a FLOAT.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.FLOAT.params.precision"></span><strong>precision</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.FLOAT.params.precision">¶</a> – Total digits in this number. If scale and precision
are both None, values are stored to limits allowed by the server.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.FLOAT.params.scale"></span><strong>scale</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.FLOAT.params.scale">¶</a> – The number of digits after the decimal point.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.FLOAT.params.unsigned"></span><strong>unsigned</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.FLOAT.params.unsigned">¶</a> – a boolean, optional.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.FLOAT.params.zerofill"></span><strong>zerofill</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.FLOAT.params.zerofill">¶</a> – Optional. If true, values will be stored as strings
left-padded with zeros. Note that this does not effect the values
returned by the underlying database API, which continue to be
numeric.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.INTEGER">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">INTEGER</tt><big>(</big><em>display_width=None</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.INTEGER" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.dialects.mysql.base._IntegerType</span></tt>, <a class="reference internal" href="../core/types.html#sqlalchemy.types.INTEGER" title="sqlalchemy.types.INTEGER"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types.INTEGER</span></tt></a></p>
<p>MySQL INTEGER type.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.INTEGER.__init__">
<tt class="descname">__init__</tt><big>(</big><em>display_width=None</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.INTEGER.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct an INTEGER.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.INTEGER.params.display_width"></span><strong>display_width</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.INTEGER.params.display_width">¶</a> – Optional, maximum display width for this number.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.INTEGER.params.unsigned"></span><strong>unsigned</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.INTEGER.params.unsigned">¶</a> – a boolean, optional.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.INTEGER.params.zerofill"></span><strong>zerofill</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.INTEGER.params.zerofill">¶</a> – Optional. If true, values will be stored as strings
left-padded with zeros. Note that this does not effect the values
returned by the underlying database API, which continue to be
numeric.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.LONGBLOB">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">LONGBLOB</tt><big>(</big><em>length=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.LONGBLOB" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types._Binary</span></tt></p>
<p>MySQL LONGBLOB type, for binary data up to 2^32 bytes.</p>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.LONGTEXT">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">LONGTEXT</tt><big>(</big><em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.LONGTEXT" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.dialects.mysql.base._StringType</span></tt></p>
<p>MySQL LONGTEXT type, for text up to 2^32 characters.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.LONGTEXT.__init__">
<tt class="descname">__init__</tt><big>(</big><em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.LONGTEXT.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a LONGTEXT.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.LONGTEXT.params.charset"></span><strong>charset</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.LONGTEXT.params.charset">¶</a> – Optional, a column-level character set for this string
value. Takes precedence to ‘ascii’ or ‘unicode’ short-hand.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.LONGTEXT.params.collation"></span><strong>collation</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.LONGTEXT.params.collation">¶</a> – Optional, a column-level collation for this string
value. Takes precedence to ‘binary’ short-hand.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.LONGTEXT.params.ascii"></span><strong>ascii</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.LONGTEXT.params.ascii">¶</a> – Defaults to False: short-hand for the <tt class="docutils literal"><span class="pre">latin1</span></tt>
character set, generates ASCII in schema.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.LONGTEXT.params.unicode"></span><strong>unicode</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.LONGTEXT.params.unicode">¶</a> – Defaults to False: short-hand for the <tt class="docutils literal"><span class="pre">ucs2</span></tt>
character set, generates UNICODE in schema.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.LONGTEXT.params.national"></span><strong>national</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.LONGTEXT.params.national">¶</a> – Optional. If true, use the server’s configured
national character set.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.LONGTEXT.params.binary"></span><strong>binary</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.LONGTEXT.params.binary">¶</a> – Defaults to False: short-hand, pick the binary
collation type that matches the column’s character set. Generates
BINARY in schema. This does not affect the type of data stored,
only the collation of character data.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.MEDIUMBLOB">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">MEDIUMBLOB</tt><big>(</big><em>length=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.MEDIUMBLOB" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types._Binary</span></tt></p>
<p>MySQL MEDIUMBLOB type, for binary data up to 2^24 bytes.</p>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.MEDIUMINT">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">MEDIUMINT</tt><big>(</big><em>display_width=None</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.MEDIUMINT" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.dialects.mysql.base._IntegerType</span></tt></p>
<p>MySQL MEDIUMINTEGER type.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.MEDIUMINT.__init__">
<tt class="descname">__init__</tt><big>(</big><em>display_width=None</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.MEDIUMINT.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a MEDIUMINTEGER</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.MEDIUMINT.params.display_width"></span><strong>display_width</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.MEDIUMINT.params.display_width">¶</a> – Optional, maximum display width for this number.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.MEDIUMINT.params.unsigned"></span><strong>unsigned</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.MEDIUMINT.params.unsigned">¶</a> – a boolean, optional.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.MEDIUMINT.params.zerofill"></span><strong>zerofill</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.MEDIUMINT.params.zerofill">¶</a> – Optional. If true, values will be stored as strings
left-padded with zeros. Note that this does not effect the values
returned by the underlying database API, which continue to be
numeric.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.MEDIUMTEXT">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">MEDIUMTEXT</tt><big>(</big><em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.MEDIUMTEXT" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.dialects.mysql.base._StringType</span></tt></p>
<p>MySQL MEDIUMTEXT type, for text up to 2^24 characters.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.MEDIUMTEXT.__init__">
<tt class="descname">__init__</tt><big>(</big><em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.MEDIUMTEXT.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a MEDIUMTEXT.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.MEDIUMTEXT.params.charset"></span><strong>charset</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.MEDIUMTEXT.params.charset">¶</a> – Optional, a column-level character set for this string
value. Takes precedence to ‘ascii’ or ‘unicode’ short-hand.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.MEDIUMTEXT.params.collation"></span><strong>collation</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.MEDIUMTEXT.params.collation">¶</a> – Optional, a column-level collation for this string
value. Takes precedence to ‘binary’ short-hand.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.MEDIUMTEXT.params.ascii"></span><strong>ascii</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.MEDIUMTEXT.params.ascii">¶</a> – Defaults to False: short-hand for the <tt class="docutils literal"><span class="pre">latin1</span></tt>
character set, generates ASCII in schema.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.MEDIUMTEXT.params.unicode"></span><strong>unicode</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.MEDIUMTEXT.params.unicode">¶</a> – Defaults to False: short-hand for the <tt class="docutils literal"><span class="pre">ucs2</span></tt>
character set, generates UNICODE in schema.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.MEDIUMTEXT.params.national"></span><strong>national</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.MEDIUMTEXT.params.national">¶</a> – Optional. If true, use the server’s configured
national character set.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.MEDIUMTEXT.params.binary"></span><strong>binary</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.MEDIUMTEXT.params.binary">¶</a> – Defaults to False: short-hand, pick the binary
collation type that matches the column’s character set. Generates
BINARY in schema. This does not affect the type of data stored,
only the collation of character data.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.NCHAR">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">NCHAR</tt><big>(</big><em>length=None</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.NCHAR" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.dialects.mysql.base._StringType</span></tt>, <a class="reference internal" href="../core/types.html#sqlalchemy.types.NCHAR" title="sqlalchemy.types.NCHAR"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types.NCHAR</span></tt></a></p>
<p>MySQL NCHAR type.</p>
<p>For fixed-length character data in the server’s configured national
character set.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.NCHAR.__init__">
<tt class="descname">__init__</tt><big>(</big><em>length=None</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.NCHAR.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct an NCHAR.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.NCHAR.params.length"></span><strong>length</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.NCHAR.params.length">¶</a> – Maximum data length, in characters.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.NCHAR.params.binary"></span><strong>binary</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.NCHAR.params.binary">¶</a> – Optional, use the default binary collation for the
national character set. This does not affect the type of data
stored, use a BINARY type for binary data.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.NCHAR.params.collation"></span><strong>collation</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.NCHAR.params.collation">¶</a> – Optional, request a particular collation. Must be
compatible with the national character set.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.NUMERIC">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">NUMERIC</tt><big>(</big><em>precision=None</em>, <em>scale=None</em>, <em>asdecimal=True</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.NUMERIC" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.dialects.mysql.base._NumericType</span></tt>, <a class="reference internal" href="../core/types.html#sqlalchemy.types.NUMERIC" title="sqlalchemy.types.NUMERIC"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types.NUMERIC</span></tt></a></p>
<p>MySQL NUMERIC type.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.NUMERIC.__init__">
<tt class="descname">__init__</tt><big>(</big><em>precision=None</em>, <em>scale=None</em>, <em>asdecimal=True</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.NUMERIC.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a NUMERIC.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.NUMERIC.params.precision"></span><strong>precision</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.NUMERIC.params.precision">¶</a> – Total digits in this number. If scale and precision
are both None, values are stored to limits allowed by the server.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.NUMERIC.params.scale"></span><strong>scale</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.NUMERIC.params.scale">¶</a> – The number of digits after the decimal point.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.NUMERIC.params.unsigned"></span><strong>unsigned</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.NUMERIC.params.unsigned">¶</a> – a boolean, optional.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.NUMERIC.params.zerofill"></span><strong>zerofill</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.NUMERIC.params.zerofill">¶</a> – Optional. If true, values will be stored as strings
left-padded with zeros. Note that this does not effect the values
returned by the underlying database API, which continue to be
numeric.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.NVARCHAR">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">NVARCHAR</tt><big>(</big><em>length=None</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.NVARCHAR" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.dialects.mysql.base._StringType</span></tt>, <a class="reference internal" href="../core/types.html#sqlalchemy.types.NVARCHAR" title="sqlalchemy.types.NVARCHAR"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types.NVARCHAR</span></tt></a></p>
<p>MySQL NVARCHAR type.</p>
<p>For variable-length character data in the server’s configured national
character set.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.NVARCHAR.__init__">
<tt class="descname">__init__</tt><big>(</big><em>length=None</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.NVARCHAR.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct an NVARCHAR.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.NVARCHAR.params.length"></span><strong>length</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.NVARCHAR.params.length">¶</a> – Maximum data length, in characters.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.NVARCHAR.params.binary"></span><strong>binary</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.NVARCHAR.params.binary">¶</a> – Optional, use the default binary collation for the
national character set. This does not affect the type of data
stored, use a BINARY type for binary data.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.NVARCHAR.params.collation"></span><strong>collation</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.NVARCHAR.params.collation">¶</a> – Optional, request a particular collation. Must be
compatible with the national character set.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.REAL">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">REAL</tt><big>(</big><em>precision=None</em>, <em>scale=None</em>, <em>asdecimal=True</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.REAL" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.dialects.mysql.base._FloatType</span></tt>, <a class="reference internal" href="../core/types.html#sqlalchemy.types.REAL" title="sqlalchemy.types.REAL"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types.REAL</span></tt></a></p>
<p>MySQL REAL type.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.REAL.__init__">
<tt class="descname">__init__</tt><big>(</big><em>precision=None</em>, <em>scale=None</em>, <em>asdecimal=True</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.REAL.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a REAL.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">The <a class="reference internal" href="#sqlalchemy.dialects.mysql.REAL" title="sqlalchemy.dialects.mysql.REAL"><tt class="xref py py-class docutils literal"><span class="pre">REAL</span></tt></a> type by default converts from float
to Decimal, using a truncation that defaults to 10 digits.
Specify either <tt class="docutils literal"><span class="pre">scale=n</span></tt> or <tt class="docutils literal"><span class="pre">decimal_return_scale=n</span></tt> in order
to change this scale, or <tt class="docutils literal"><span class="pre">asdecimal=False</span></tt> to return values
directly as Python floating points.</p>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.REAL.params.precision"></span><strong>precision</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.REAL.params.precision">¶</a> – Total digits in this number. If scale and precision
are both None, values are stored to limits allowed by the server.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.REAL.params.scale"></span><strong>scale</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.REAL.params.scale">¶</a> – The number of digits after the decimal point.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.REAL.params.unsigned"></span><strong>unsigned</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.REAL.params.unsigned">¶</a> – a boolean, optional.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.REAL.params.zerofill"></span><strong>zerofill</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.REAL.params.zerofill">¶</a> – Optional. If true, values will be stored as strings
left-padded with zeros. Note that this does not effect the values
returned by the underlying database API, which continue to be
numeric.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.SET">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">SET</tt><big>(</big><em>*values</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.SET" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.dialects.mysql.base._EnumeratedValues</span></tt></p>
<p>MySQL SET type.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.SET.__init__">
<tt class="descname">__init__</tt><big>(</big><em>*values</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.SET.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a SET.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">Column</span><span class="p">(</span><span class="s">'myset'</span><span class="p">,</span> <span class="n">SET</span><span class="p">(</span><span class="s">"foo"</span><span class="p">,</span> <span class="s">"bar"</span><span class="p">,</span> <span class="s">"baz"</span><span class="p">))</span></pre></div>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.SET.params.values"></span><strong>values</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.SET.params.values">¶</a> – <p>The range of valid values for this SET. Values will be
quoted when generating the schema according to the quoting flag (see
below).</p>
<div class="versionchanged">
<p><span>Changed in version 0.9.0: </span>quoting is applied automatically to
<a class="reference internal" href="#sqlalchemy.dialects.mysql.SET" title="sqlalchemy.dialects.mysql.SET"><tt class="xref py py-class docutils literal"><span class="pre">mysql.SET</span></tt></a> in the same way as for <a class="reference internal" href="#sqlalchemy.dialects.mysql.ENUM" title="sqlalchemy.dialects.mysql.ENUM"><tt class="xref py py-class docutils literal"><span class="pre">mysql.ENUM</span></tt></a>.</p>
</div>
</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.SET.params.charset"></span><strong>charset</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.SET.params.charset">¶</a> – Optional, a column-level character set for this string
value. Takes precedence to ‘ascii’ or ‘unicode’ short-hand.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.SET.params.collation"></span><strong>collation</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.SET.params.collation">¶</a> – Optional, a column-level collation for this string
value. Takes precedence to ‘binary’ short-hand.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.SET.params.ascii"></span><strong>ascii</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.SET.params.ascii">¶</a> – Defaults to False: short-hand for the <tt class="docutils literal"><span class="pre">latin1</span></tt>
character set, generates ASCII in schema.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.SET.params.unicode"></span><strong>unicode</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.SET.params.unicode">¶</a> – Defaults to False: short-hand for the <tt class="docutils literal"><span class="pre">ucs2</span></tt>
character set, generates UNICODE in schema.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.SET.params.binary"></span><strong>binary</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.SET.params.binary">¶</a> – Defaults to False: short-hand, pick the binary
collation type that matches the column’s character set. Generates
BINARY in schema. This does not affect the type of data stored,
only the collation of character data.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.SET.params.quoting"></span><strong>quoting</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.SET.params.quoting">¶</a> – <p>Defaults to ‘auto’: automatically determine enum value
quoting. If all enum values are surrounded by the same quoting
character, then use ‘quoted’ mode. Otherwise, use ‘unquoted’ mode.</p>
<p>‘quoted’: values in enums are already quoted, they will be used
directly when generating the schema - this usage is deprecated.</p>
<p>‘unquoted’: values in enums are not quoted, they will be escaped and
surrounded by single quotes when generating the schema.</p>
<p>Previous versions of this type always required manually quoted
values to be supplied; future versions will always quote the string
literals for you. This is a transitional option.</p>
<div class="versionadded">
<p><span>New in version 0.9.0.</span></p>
</div>
</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.SMALLINT">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">SMALLINT</tt><big>(</big><em>display_width=None</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.SMALLINT" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.dialects.mysql.base._IntegerType</span></tt>, <a class="reference internal" href="../core/types.html#sqlalchemy.types.SMALLINT" title="sqlalchemy.types.SMALLINT"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types.SMALLINT</span></tt></a></p>
<p>MySQL SMALLINTEGER type.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.SMALLINT.__init__">
<tt class="descname">__init__</tt><big>(</big><em>display_width=None</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.SMALLINT.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a SMALLINTEGER.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.SMALLINT.params.display_width"></span><strong>display_width</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.SMALLINT.params.display_width">¶</a> – Optional, maximum display width for this number.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.SMALLINT.params.unsigned"></span><strong>unsigned</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.SMALLINT.params.unsigned">¶</a> – a boolean, optional.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.SMALLINT.params.zerofill"></span><strong>zerofill</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.SMALLINT.params.zerofill">¶</a> – Optional. If true, values will be stored as strings
left-padded with zeros. Note that this does not effect the values
returned by the underlying database API, which continue to be
numeric.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.TEXT">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">TEXT</tt><big>(</big><em>length=None</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.TEXT" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.dialects.mysql.base._StringType</span></tt>, <a class="reference internal" href="../core/types.html#sqlalchemy.types.TEXT" title="sqlalchemy.types.TEXT"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types.TEXT</span></tt></a></p>
<p>MySQL TEXT type, for text up to 2^16 characters.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.TEXT.__init__">
<tt class="descname">__init__</tt><big>(</big><em>length=None</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.TEXT.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a TEXT.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.TEXT.params.length"></span><strong>length</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.TEXT.params.length">¶</a> – Optional, if provided the server may optimize storage
by substituting the smallest TEXT type sufficient to store
<tt class="docutils literal"><span class="pre">length</span></tt> characters.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.TEXT.params.charset"></span><strong>charset</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.TEXT.params.charset">¶</a> – Optional, a column-level character set for this string
value. Takes precedence to ‘ascii’ or ‘unicode’ short-hand.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.TEXT.params.collation"></span><strong>collation</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.TEXT.params.collation">¶</a> – Optional, a column-level collation for this string
value. Takes precedence to ‘binary’ short-hand.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.TEXT.params.ascii"></span><strong>ascii</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.TEXT.params.ascii">¶</a> – Defaults to False: short-hand for the <tt class="docutils literal"><span class="pre">latin1</span></tt>
character set, generates ASCII in schema.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.TEXT.params.unicode"></span><strong>unicode</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.TEXT.params.unicode">¶</a> – Defaults to False: short-hand for the <tt class="docutils literal"><span class="pre">ucs2</span></tt>
character set, generates UNICODE in schema.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.TEXT.params.national"></span><strong>national</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.TEXT.params.national">¶</a> – Optional. If true, use the server’s configured
national character set.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.TEXT.params.binary"></span><strong>binary</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.TEXT.params.binary">¶</a> – Defaults to False: short-hand, pick the binary
collation type that matches the column’s character set. Generates
BINARY in schema. This does not affect the type of data stored,
only the collation of character data.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.TIME">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">TIME</tt><big>(</big><em>timezone=False</em>, <em>fsp=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.TIME" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <a class="reference internal" href="../core/types.html#sqlalchemy.types.TIME" title="sqlalchemy.types.TIME"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types.TIME</span></tt></a></p>
<p>MySQL TIME type.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.TIME.__init__">
<tt class="descname">__init__</tt><big>(</big><em>timezone=False</em>, <em>fsp=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.TIME.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a MySQL TIME type.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.TIME.params.timezone"></span><strong>timezone</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.TIME.params.timezone">¶</a> – not used by the MySQL dialect.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.TIME.params.fsp"></span><strong>fsp</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.TIME.params.fsp">¶</a> – <p>fractional seconds precision value.
MySQL 5.6 supports storage of fractional seconds;
this parameter will be used when emitting DDL
for the TIME type.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">DBAPI driver support for fractional seconds may
be limited; current support includes
MySQL Connector/Python.</p>
</div>
</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="versionadded">
<p><span>New in version 0.8: </span>The MySQL-specific TIME
type as well as fractional seconds support.</p>
</div>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.TIMESTAMP">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">TIMESTAMP</tt><big>(</big><em>timezone=False</em>, <em>fsp=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.TIMESTAMP" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <a class="reference internal" href="../core/types.html#sqlalchemy.types.TIMESTAMP" title="sqlalchemy.types.TIMESTAMP"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types.TIMESTAMP</span></tt></a></p>
<p>MySQL TIMESTAMP type.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.TIMESTAMP.__init__">
<tt class="descname">__init__</tt><big>(</big><em>timezone=False</em>, <em>fsp=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.TIMESTAMP.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a MySQL TIMESTAMP type.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.TIMESTAMP.params.timezone"></span><strong>timezone</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.TIMESTAMP.params.timezone">¶</a> – not used by the MySQL dialect.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.TIMESTAMP.params.fsp"></span><strong>fsp</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.TIMESTAMP.params.fsp">¶</a> – <p>fractional seconds precision value.
MySQL 5.6.4 supports storage of fractional seconds;
this parameter will be used when emitting DDL
for the TIMESTAMP type.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">DBAPI driver support for fractional seconds may
be limited; current support includes
MySQL Connector/Python.</p>
</div>
</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="versionadded">
<p><span>New in version 0.8.5: </span>Added MySQL-specific <a class="reference internal" href="#sqlalchemy.dialects.mysql.TIMESTAMP" title="sqlalchemy.dialects.mysql.TIMESTAMP"><tt class="xref py py-class docutils literal"><span class="pre">mysql.TIMESTAMP</span></tt></a>
with fractional seconds support.</p>
</div>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.TINYBLOB">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">TINYBLOB</tt><big>(</big><em>length=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.TINYBLOB" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types._Binary</span></tt></p>
<p>MySQL TINYBLOB type, for binary data up to 2^8 bytes.</p>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.TINYINT">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">TINYINT</tt><big>(</big><em>display_width=None</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.TINYINT" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.dialects.mysql.base._IntegerType</span></tt></p>
<p>MySQL TINYINT type.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.TINYINT.__init__">
<tt class="descname">__init__</tt><big>(</big><em>display_width=None</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.TINYINT.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a TINYINT.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.TINYINT.params.display_width"></span><strong>display_width</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.TINYINT.params.display_width">¶</a> – Optional, maximum display width for this number.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.TINYINT.params.unsigned"></span><strong>unsigned</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.TINYINT.params.unsigned">¶</a> – a boolean, optional.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.TINYINT.params.zerofill"></span><strong>zerofill</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.TINYINT.params.zerofill">¶</a> – Optional. If true, values will be stored as strings
left-padded with zeros. Note that this does not effect the values
returned by the underlying database API, which continue to be
numeric.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.TINYTEXT">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">TINYTEXT</tt><big>(</big><em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.TINYTEXT" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.dialects.mysql.base._StringType</span></tt></p>
<p>MySQL TINYTEXT type, for text up to 2^8 characters.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.TINYTEXT.__init__">
<tt class="descname">__init__</tt><big>(</big><em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.TINYTEXT.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a TINYTEXT.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.TINYTEXT.params.charset"></span><strong>charset</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.TINYTEXT.params.charset">¶</a> – Optional, a column-level character set for this string
value. Takes precedence to ‘ascii’ or ‘unicode’ short-hand.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.TINYTEXT.params.collation"></span><strong>collation</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.TINYTEXT.params.collation">¶</a> – Optional, a column-level collation for this string
value. Takes precedence to ‘binary’ short-hand.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.TINYTEXT.params.ascii"></span><strong>ascii</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.TINYTEXT.params.ascii">¶</a> – Defaults to False: short-hand for the <tt class="docutils literal"><span class="pre">latin1</span></tt>
character set, generates ASCII in schema.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.TINYTEXT.params.unicode"></span><strong>unicode</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.TINYTEXT.params.unicode">¶</a> – Defaults to False: short-hand for the <tt class="docutils literal"><span class="pre">ucs2</span></tt>
character set, generates UNICODE in schema.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.TINYTEXT.params.national"></span><strong>national</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.TINYTEXT.params.national">¶</a> – Optional. If true, use the server’s configured
national character set.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.TINYTEXT.params.binary"></span><strong>binary</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.TINYTEXT.params.binary">¶</a> – Defaults to False: short-hand, pick the binary
collation type that matches the column’s character set. Generates
BINARY in schema. This does not affect the type of data stored,
only the collation of character data.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.VARBINARY">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">VARBINARY</tt><big>(</big><em>length=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.VARBINARY" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types._Binary</span></tt></p>
<p>The SQL VARBINARY type.</p>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.VARCHAR">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">VARCHAR</tt><big>(</big><em>length=None</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.VARCHAR" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.dialects.mysql.base._StringType</span></tt>, <a class="reference internal" href="../core/types.html#sqlalchemy.types.VARCHAR" title="sqlalchemy.types.VARCHAR"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types.VARCHAR</span></tt></a></p>
<p>MySQL VARCHAR type, for variable-length character data.</p>
<dl class="method">
<dt id="sqlalchemy.dialects.mysql.VARCHAR.__init__">
<tt class="descname">__init__</tt><big>(</big><em>length=None</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.VARCHAR.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a VARCHAR.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.dialects.mysql.VARCHAR.params.charset"></span><strong>charset</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.VARCHAR.params.charset">¶</a> – Optional, a column-level character set for this string
value. Takes precedence to ‘ascii’ or ‘unicode’ short-hand.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.VARCHAR.params.collation"></span><strong>collation</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.VARCHAR.params.collation">¶</a> – Optional, a column-level collation for this string
value. Takes precedence to ‘binary’ short-hand.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.VARCHAR.params.ascii"></span><strong>ascii</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.VARCHAR.params.ascii">¶</a> – Defaults to False: short-hand for the <tt class="docutils literal"><span class="pre">latin1</span></tt>
character set, generates ASCII in schema.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.VARCHAR.params.unicode"></span><strong>unicode</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.VARCHAR.params.unicode">¶</a> – Defaults to False: short-hand for the <tt class="docutils literal"><span class="pre">ucs2</span></tt>
character set, generates UNICODE in schema.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.VARCHAR.params.national"></span><strong>national</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.VARCHAR.params.national">¶</a> – Optional. If true, use the server’s configured
national character set.</li>
<li><span class="target" id="sqlalchemy.dialects.mysql.VARCHAR.params.binary"></span><strong>binary</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.dialects.mysql.VARCHAR.params.binary">¶</a> – Defaults to False: short-hand, pick the binary
collation type that matches the column’s character set. Generates
BINARY in schema. This does not affect the type of data stored,
only the collation of character data.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.dialects.mysql.YEAR">
<em class="property">class </em><tt class="descclassname">sqlalchemy.dialects.mysql.</tt><tt class="descname">YEAR</tt><big>(</big><em>display_width=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.dialects.mysql.YEAR" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <a class="reference internal" href="../core/types.html#sqlalchemy.types.TypeEngine" title="sqlalchemy.types.TypeEngine"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.types.TypeEngine</span></tt></a></p>
<p>MySQL YEAR type, for single byte storage of years 1901-2155.</p>
</dd></dl>
</div>
<div class="section" id="module-sqlalchemy.dialects.mysql.mysqldb">
<span id="mysql-python"></span><h2>MySQL-Python<a class="headerlink" href="#module-sqlalchemy.dialects.mysql.mysqldb" title="Permalink to this headline">¶</a></h2>
<p>Support for the MySQL database via the MySQL-Python driver.</p>
<div class="section" id="dialect-mysql-mysqldb-url">
<h3>DBAPI<a class="headerlink" href="#dialect-mysql-mysqldb-url" title="Permalink to this headline">¶</a></h3>
<p>Documentation and download information (if applicable) for MySQL-Python is available at:
<a class="reference external" href="http://sourceforge.net/projects/mysql-python">http://sourceforge.net/projects/mysql-python</a></p>
</div>
<div class="section" id="dialect-mysql-mysqldb-connect">
<h3>Connecting<a class="headerlink" href="#dialect-mysql-mysqldb-connect" title="Permalink to this headline">¶</a></h3>
<p>Connect String:<div class="highlight-python"><pre>mysql+mysqldb://<user>:<password>@<host>[:<port>]/<dbname></pre>
</div>
</p>
</div>
<div class="section" id="unicode">
<h3>Unicode<a class="headerlink" href="#unicode" title="Permalink to this headline">¶</a></h3>
<p>MySQLdb requires a “charset” parameter to be passed in order for it
to handle non-ASCII characters correctly. When this parameter is passed,
MySQLdb will also implicitly set the “use_unicode” flag to true, which means
that it will return Python unicode objects instead of bytestrings.
However, SQLAlchemy’s decode process, when C extensions are enabled,
is orders of magnitude faster than that of MySQLdb as it does not call into
Python functions to do so. Therefore, the <strong>recommended URL to use for
unicode</strong> will include both charset and use_unicode=0:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">create_engine</span><span class="p">(</span><span class="s">"mysql+mysqldb://user:pass@host/dbname?charset=utf8&use_unicode=0"</span><span class="p">)</span></pre></div>
</div>
<p>As of this writing, MySQLdb only runs on Python 2. It is not known how
MySQLdb behaves on Python 3 as far as unicode decoding.</p>
</div>
<div class="section" id="known-issues">
<h3>Known Issues<a class="headerlink" href="#known-issues" title="Permalink to this headline">¶</a></h3>
<p>MySQL-python version 1.2.2 has a serious memory leak related
to unicode conversion, a feature which is disabled via <tt class="docutils literal"><span class="pre">use_unicode=0</span></tt>.
It is strongly advised to use the latest version of MySQL-Python.</p>
</div>
</div>
<div class="section" id="module-sqlalchemy.dialects.mysql.oursql">
<span id="oursql"></span><h2>OurSQL<a class="headerlink" href="#module-sqlalchemy.dialects.mysql.oursql" title="Permalink to this headline">¶</a></h2>
<p>Support for the MySQL database via the OurSQL driver.</p>
<div class="section" id="dialect-mysql-oursql-url">
<h3>DBAPI<a class="headerlink" href="#dialect-mysql-oursql-url" title="Permalink to this headline">¶</a></h3>
<p>Documentation and download information (if applicable) for OurSQL is available at:
<a class="reference external" href="http://packages.python.org/oursql/">http://packages.python.org/oursql/</a></p>
</div>
<div class="section" id="dialect-mysql-oursql-connect">
<h3>Connecting<a class="headerlink" href="#dialect-mysql-oursql-connect" title="Permalink to this headline">¶</a></h3>
<p>Connect String:<div class="highlight-python"><pre>mysql+oursql://<user>:<password>@<host>[:<port>]/<dbname></pre>
</div>
</p>
</div>
<div class="section" id="id2">
<h3>Unicode<a class="headerlink" href="#id2" title="Permalink to this headline">¶</a></h3>
<p>oursql defaults to using <tt class="docutils literal"><span class="pre">utf8</span></tt> as the connection charset, but other
encodings may be used instead. Like the MySQL-Python driver, unicode support
can be completely disabled:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="c"># oursql sets the connection charset to utf8 automatically; all strings come</span>
<span class="c"># back as utf8 str</span>
<span class="n">create_engine</span><span class="p">(</span><span class="s">'mysql+oursql:///mydb?use_unicode=0'</span><span class="p">)</span></pre></div>
</div>
<p>To not automatically use <tt class="docutils literal"><span class="pre">utf8</span></tt> and instead use whatever the connection
defaults to, there is a separate parameter:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="c"># use the default connection charset; all strings come back as unicode</span>
<span class="n">create_engine</span><span class="p">(</span><span class="s">'mysql+oursql:///mydb?default_charset=1'</span><span class="p">)</span>
<span class="c"># use latin1 as the connection charset; all strings come back as unicode</span>
<span class="n">create_engine</span><span class="p">(</span><span class="s">'mysql+oursql:///mydb?charset=latin1'</span><span class="p">)</span></pre></div>
</div>
</div>
</div>
<div class="section" id="module-sqlalchemy.dialects.mysql.pymysql">
<span id="pymysql"></span><h2>pymysql<a class="headerlink" href="#module-sqlalchemy.dialects.mysql.pymysql" title="Permalink to this headline">¶</a></h2>
<p>Support for the MySQL database via the PyMySQL driver.</p>
<div class="section" id="dialect-mysql-pymysql-url">
<h3>DBAPI<a class="headerlink" href="#dialect-mysql-pymysql-url" title="Permalink to this headline">¶</a></h3>
<p>Documentation and download information (if applicable) for PyMySQL is available at:
<a class="reference external" href="http://code.google.com/p/pymysql/">http://code.google.com/p/pymysql/</a></p>
</div>
<div class="section" id="dialect-mysql-pymysql-connect">
<h3>Connecting<a class="headerlink" href="#dialect-mysql-pymysql-connect" title="Permalink to this headline">¶</a></h3>
<p>Connect String:<div class="highlight-python"><pre>mysql+pymysql://<username>:<password>@<host>/<dbname>[?<options>]</pre>
</div>
</p>
</div>
<div class="section" id="mysql-python-compatibility">
<h3>MySQL-Python Compatibility<a class="headerlink" href="#mysql-python-compatibility" title="Permalink to this headline">¶</a></h3>
<p>The pymysql DBAPI is a pure Python port of the MySQL-python (MySQLdb) driver,
and targets 100% compatibility. Most behavioral notes for MySQL-python apply
to the pymysql driver as well.</p>
</div>
</div>
<div class="section" id="module-sqlalchemy.dialects.mysql.mysqlconnector">
<span id="mysql-connector"></span><h2>MySQL-Connector<a class="headerlink" href="#module-sqlalchemy.dialects.mysql.mysqlconnector" title="Permalink to this headline">¶</a></h2>
<p>Support for the MySQL database via the MySQL Connector/Python driver.</p>
<div class="section" id="dialect-mysql-mysqlconnector-url">
<h3>DBAPI<a class="headerlink" href="#dialect-mysql-mysqlconnector-url" title="Permalink to this headline">¶</a></h3>
<p>Documentation and download information (if applicable) for MySQL Connector/Python is available at:
<a class="reference external" href="http://dev.mysql.com/downloads/connector/python/">http://dev.mysql.com/downloads/connector/python/</a></p>
</div>
<div class="section" id="dialect-mysql-mysqlconnector-connect">
<h3>Connecting<a class="headerlink" href="#dialect-mysql-mysqlconnector-connect" title="Permalink to this headline">¶</a></h3>
<p>Connect String:<div class="highlight-python"><pre>mysql+mysqlconnector://<user>:<password>@<host>[:<port>]/<dbname></pre>
</div>
</p>
</div>
</div>
<div class="section" id="module-sqlalchemy.dialects.mysql.cymysql">
<span id="cymysql"></span><h2>cymysql<a class="headerlink" href="#module-sqlalchemy.dialects.mysql.cymysql" title="Permalink to this headline">¶</a></h2>
<p>Support for the MySQL database via the CyMySQL driver.</p>
<div class="section" id="dialect-mysql-cymysql-url">
<h3>DBAPI<a class="headerlink" href="#dialect-mysql-cymysql-url" title="Permalink to this headline">¶</a></h3>
<p>Documentation and download information (if applicable) for CyMySQL is available at:
<a class="reference external" href="https://github.com/nakagami/CyMySQL">https://github.com/nakagami/CyMySQL</a></p>
</div>
<div class="section" id="dialect-mysql-cymysql-connect">
<h3>Connecting<a class="headerlink" href="#dialect-mysql-cymysql-connect" title="Permalink to this headline">¶</a></h3>
<p>Connect String:<div class="highlight-python"><pre>mysql+cymysql://<username>:<password>@<host>/<dbname>[?<options>]</pre>
</div>
</p>
</div>
</div>
<div class="section" id="module-sqlalchemy.dialects.mysql.gaerdbms">
<span id="google-app-engine"></span><h2>Google App Engine<a class="headerlink" href="#module-sqlalchemy.dialects.mysql.gaerdbms" title="Permalink to this headline">¶</a></h2>
<p>Support for the MySQL database via the Google Cloud SQL driver.<p>This dialect is based primarily on the <a class="reference internal" href="#module-sqlalchemy.dialects.mysql.mysqldb" title="sqlalchemy.dialects.mysql.mysqldb"><tt class="xref py py-mod docutils literal"><span class="pre">mysql.mysqldb</span></tt></a> dialect with
minimal changes.</p>
<div class="versionadded">
<p><span>New in version 0.7.8.</span></p>
</div>
</p>
<div class="section" id="dialect-mysql-gaerdbms-url">
<h3>DBAPI<a class="headerlink" href="#dialect-mysql-gaerdbms-url" title="Permalink to this headline">¶</a></h3>
<p>Documentation and download information (if applicable) for Google Cloud SQL is available at:
<a class="reference external" href="https://developers.google.com/appengine/docs/python/cloud-sql/developers-guide">https://developers.google.com/appengine/docs/python/cloud-sql/developers-guide</a></p>
</div>
<div class="section" id="dialect-mysql-gaerdbms-connect">
<h3>Connecting<a class="headerlink" href="#dialect-mysql-gaerdbms-connect" title="Permalink to this headline">¶</a></h3>
<p>Connect String:<div class="highlight-python"><pre>mysql+gaerdbms:///<dbname>?instance=<instancename></pre>
</div>
</p>
</div>
<div class="section" id="pooling">
<h3>Pooling<a class="headerlink" href="#pooling" title="Permalink to this headline">¶</a></h3>
<p>Google App Engine connections appear to be randomly recycled,
so the dialect does not pool connections. The <a class="reference internal" href="../core/pooling.html#sqlalchemy.pool.NullPool" title="sqlalchemy.pool.NullPool"><tt class="xref py py-class docutils literal"><span class="pre">NullPool</span></tt></a>
implementation is installed within the <a class="reference internal" href="../core/connections.html#sqlalchemy.engine.Engine" title="sqlalchemy.engine.Engine"><tt class="xref py py-class docutils literal"><span class="pre">Engine</span></tt></a> by
default.</p>
</div>
</div>
<div class="section" id="module-sqlalchemy.dialects.mysql.pyodbc">
<span id="pyodbc"></span><h2>pyodbc<a class="headerlink" href="#module-sqlalchemy.dialects.mysql.pyodbc" title="Permalink to this headline">¶</a></h2>
<p>Support for the MySQL database via the PyODBC driver.</p>
<div class="section" id="dialect-mysql-pyodbc-url">
<h3>DBAPI<a class="headerlink" href="#dialect-mysql-pyodbc-url" title="Permalink to this headline">¶</a></h3>
<p>Documentation and download information (if applicable) for PyODBC is available at:
<a class="reference external" href="http://pypi.python.org/pypi/pyodbc/">http://pypi.python.org/pypi/pyodbc/</a></p>
</div>
<div class="section" id="dialect-mysql-pyodbc-connect">
<h3>Connecting<a class="headerlink" href="#dialect-mysql-pyodbc-connect" title="Permalink to this headline">¶</a></h3>
<p>Connect String:<div class="highlight-python"><pre>mysql+pyodbc://<username>:<password>@<dsnname></pre>
</div>
</p>
</div>
<div class="section" id="limitations">
<h3>Limitations<a class="headerlink" href="#limitations" title="Permalink to this headline">¶</a></h3>
<p>The mysql-pyodbc dialect is subject to unresolved character encoding issues
which exist within the current ODBC drivers available.
(see <a class="reference external" href="http://code.google.com/p/pyodbc/issues/detail?id=25">http://code.google.com/p/pyodbc/issues/detail?id=25</a>). Consider usage
of OurSQL, MySQLdb, or MySQL-connector/Python.</p>
</div>
</div>
<div class="section" id="module-sqlalchemy.dialects.mysql.zxjdbc">
<span id="zxjdbc"></span><h2>zxjdbc<a class="headerlink" href="#module-sqlalchemy.dialects.mysql.zxjdbc" title="Permalink to this headline">¶</a></h2>
<p>Support for the MySQL database via the zxjdbc for Jython driver.</p>
<div class="section" id="dialect-mysql-zxjdbc-url">
<h3>DBAPI<a class="headerlink" href="#dialect-mysql-zxjdbc-url" title="Permalink to this headline">¶</a></h3>
<p>Drivers for this database are available at:
<a class="reference external" href="http://dev.mysql.com/downloads/connector/j/">http://dev.mysql.com/downloads/connector/j/</a></p>
</div>
<div class="section" id="dialect-mysql-zxjdbc-connect">
<h3>Connecting<a class="headerlink" href="#dialect-mysql-zxjdbc-connect" title="Permalink to this headline">¶</a></h3>
<p>Connect String:<div class="highlight-python"><pre>mysql+zxjdbc://<user>:<password>@<hostname>[:<port>]/<database></pre>
</div>
</p>
</div>
<div class="section" id="character-sets">
<h3>Character Sets<a class="headerlink" href="#character-sets" title="Permalink to this headline">¶</a></h3>
<p>SQLAlchemy zxjdbc dialects pass unicode straight through to the
zxjdbc/JDBC layer. To allow multiple character sets to be sent from the
MySQL Connector/J JDBC driver, by default SQLAlchemy sets its
<tt class="docutils literal"><span class="pre">characterEncoding</span></tt> connection property to <tt class="docutils literal"><span class="pre">UTF-8</span></tt>. It may be
overridden via a <tt class="docutils literal"><span class="pre">create_engine</span></tt> URL parameter.</p>
</div>
</div>
</div>
</div>
</div>
<div id="docs-bottom-navigation" class="docs-navigation-links">
Previous:
<a href="mssql.html" title="previous chapter">Microsoft SQL Server</a>
Next:
<a href="oracle.html" title="next chapter">Oracle</a>
<div id="docs-copyright">
© <a href="../copyright.html">Copyright</a> 2007-2014, the SQLAlchemy authors and contributors.
Created using <a href="http://sphinx.pocoo.org/">Sphinx</a> 1.2b1.
</div>
</div>
</div>
</body>
</html>
|
