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
|
---
layout: default_docs
title: Escaped scalar functions
header: Chapter 8. JDBC escapes
resource: media
previoustitle: Date-time escapes
previous: escapes-datetime.html
nexttitle: Chapter 9. PostgreSQL™ Extensions to the JDBC API
next: ext.html
---
The JDBC specification defines functions with an escape call syntax : `{fn function_name(arguments)}`.
The following tables show which functions are supported by the PostgreSQL™ driver.
The driver supports the nesting and the mixing of escaped functions and escaped
values. The appendix C of the JDBC specification describes the functions.
Some functions in the following tables are translated but not reported as supported
because they are duplicating or changing their order of the arguments. While this
is harmless for literal values or columns, it will cause problems when using
prepared statements. For example "`{fn right(?,?)}`" will be translated to "`substring(? from (length(?)+1-?))`".
As you can see the translated SQL requires more parameters than before the
translation but the driver will not automatically handle this.
<a name="escape-numeric-functions-table"></a>
**Table 8.1. Supported escaped numeric functions**
<table summary="Supported escaped numeric functions" class="CALSTABLE" border="1">
<tr>
<th>function</th>
<th>reported as supported</th>
<th>translation</th>
<th>comments</th>
</tr>
<tbody>
<tr>
<td>abs(arg1)</td>
<td>yes</td>
<td>abs(arg1)</td>
<td> </td>
</tr>
<tr>
<td>acos(arg1)</td>
<td>yes</td>
<td>acos(arg1)</td>
<td> </td>
</tr>
<tr>
<td>asin(arg1)</td>
<td>yes</td>
<td>asin(arg1)</td>
<td> </td>
</tr>
<tr>
<td>atan(arg1)</td>
<td>yes</td>
<td>atan(arg1)</td>
<td> </td>
</tr>
<tr>
<td>atan2(arg1,arg2)</td>
<td>yes</td>
<td>atan2(arg1,arg2)</td>
<td> </td>
</tr>
<tr>
<td>ceiling(arg1)</td>
<td>yes</td>
<td>ceil(arg1)</td>
<td> </td>
</tr>
<tr>
<td>cos(arg1)</td>
<td>yes</td>
<td>cos(arg1)</td>
<td> </td>
</tr>
<tr>
<td>cot(arg1)</td>
<td>yes</td>
<td>cot(arg1)</td>
<td> </td>
</tr>
<tr>
<td>degrees(arg1)</td>
<td>yes</td>
<td>degrees(arg1)</td>
<td> </td>
</tr>
<tr>
<td>exp(arg1)</td>
<td>yes</td>
<td>exp(arg1)</td>
<td> </td>
</tr>
<tr>
<td>floor(arg1)</td>
<td>yes</td>
<td>floor(arg1)</td>
<td> </td>
</tr>
<tr>
<td>log(arg1)</td>
<td>yes</td>
<td>ln(arg1)</td>
<td> </td>
</tr>
<tr>
<td>log10(arg1)</td>
<td>yes</td>
<td>log(arg1)</td>
<td> </td>
</tr>
<tr>
<td>mod(arg1,arg2)</td>
<td>yes</td>
<td>mod(arg1,arg2)</td>
<td> </td>
</tr>
<tr>
<td>pi(arg1)</td>
<td>yes</td>
<td>pi(arg1)</td>
<td> </td>
</tr>
<tr>
<td>power(arg1,arg2)</td>
<td>yes</td>
<td>pow(arg1,arg2)</td>
<td> </td>
</tr>
<tr>
<td>radians(arg1)</td>
<td>yes</td>
<td>radians(arg1)</td>
<td> </td>
</tr>
<tr>
<td>rand()</td>
<td>yes</td>
<td>random()</td>
<td> </td>
</tr>
<tr>
<td>rand(arg1)</td>
<td>yes</td>
<td>setseed(arg1)*0+random()</td>
<td>The seed is initialized with the given argument and a new randow value is returned.</td>
</tr>
<tr>
<td>round(arg1,arg2)</td>
<td>yes</td>
<td>round(arg1,arg2)</td>
<td> </td>
</tr>
<tr>
<td>sign(arg1)</td>
<td>yes</td>
<td>sign(arg1)</td>
<td> </td>
</tr>
<tr>
<td>sin(arg1)</td>
<td>yes</td>
<td>sin(arg1)</td>
<td> </td>
</tr>
<tr>
<td>sqrt(arg1)</td>
<td>yes</td>
<td>sqrt(arg1)</td>
<td> </td>
</tr>
<tr>
<td>tan(arg1)</td>
<td>yes</td>
<td>tan(arg1)</td>
<td> </td>
</tr>
<tr>
<td>truncate(arg1,arg2)</td>
<td>yes</td>
<td>trunc(arg1,arg2)</td>
<td> </td>
</tr>
</tbody>
</table>
<a name="escape-string-functions-table"></a>
**Table 8.2. Supported escaped string functions**
<table summary="Supported escaped string functions" class="CALSTABLE" border="1">
<tr>
<th>function</th>
<th>reported as supported</th>
<th>translation</th>
<th>comments</th>
</tr>
<tbody>
<tr>
<td>ascii(arg1)</td>
<td>yes</td>
<td>ascii(arg1)</td>
<td> </td>
</tr>
<tr>
<td>char(arg1)</td>
<td>yes</td>
<td>chr(arg1)</td>
<td> </td>
</tr>
<tr>
<td>concat(arg1,arg2...)</td>
<td>yes</td>
<td>(arg1||arg2...)</td>
<td>The JDBC specification
only require the two arguments version, but supporting more arguments
was so easy...</td>
</tr>
<tr>
<td>insert(arg1,arg2,arg3,arg4)</td>
<td>no</td>
<td>overlay(arg1 placing arg4 from arg2 for arg3)</td>
<td>This function is not reported as supported since it changes
the order of the arguments which can be a problem (for prepared
statements by example).</td>
</tr>
<tr>
<td>lcase(arg1)</td>
<td>yes</td>
<td>lower(arg1)</td>
<td> </td>
</tr>
<tr>
<td>left(arg1,arg2)</td>
<td>yes</td>
<td>substring(arg1 for arg2)</td>
<td> </td>
</tr>
<tr>
<td>length(arg1)</td>
<td>yes</td>
<td>length(trim(trailing from arg1))</td>
<td> </td>
</tr>
<tr>
<td>locate(arg1,arg2)</td>
<td>no</td>
<td>position(arg1 in arg2)</td>
<td> </td>
</tr>
<tr>
<td>locate(arg1,arg2,arg3)</td>
<td>no</td>
<td>(arg2*sign(position(arg1 in substring(arg2 from
arg3)+position(arg1 in substring(arg2 from arg3))</td>
<td>Not reported as supported since the three arguments version
duplicate and change the order of the arguments.</td>
</tr>
<tr>
<td>ltrim(arg1)</td>
<td>yes</td>
<td>trim(leading from arg1)</td>
<td> </td>
</tr>
<tr>
<td>repeat(arg1,arg2)</td>
<td>yes</td>
<td>repeat(arg1,arg2)</td>
<td> </td>
</tr>
<tr>
<td>replace(arg1,arg2,arg3)</td>
<td>yes</td>
<td>replace(arg1,arg2,arg3)</td>
<td>Only reported as supported by 7.3 and above servers.</td>
</tr>
<tr>
<td>right(arg1,arg2)</td>
<td>no</td>
<td>substring(arg1 from (length(arg1)+1-arg2))</td>
<td>Not reported as supported since arg2 is duplicated.</td>
</tr>
<tr>
<td>rtrim(arg1)</td>
<td>yes</td>
<td>trim(trailing from arg1)</td>
<td> </td>
</tr>
<tr>
<td>space(arg1)</td>
<td>yes</td>
<td>repeat(' ',arg1)</td>
<td> </td>
</tr>
<tr>
<td>substring(arg1,arg2)</td>
<td>yes</td>
<td>substr(arg1,arg2)</td>
<td> </td>
</tr>
<tr>
<td>substring(arg1,arg2,arg3)</td>
<td>yes</td>
<td>substr(arg1,arg2,arg3)</td>
<td> </td>
</tr>
<tr>
<td>ucase(arg1)</td>
<td>yes</td>
<td>upper(arg1)</td>
<td> </td>
</tr>
<tr>
<td>soundex(arg1)</td>
<td>no</td>
<td>soundex(arg1)</td>
<td>Not reported as supported since it requires the fuzzystrmatch
contrib module.</td>
</tr>
<tr>
<td>difference(arg1,arg2)</td>
<td>no</td>
<td>difference(arg1,arg2)</td>
<td>Not reported as supported since it requires the fuzzystrmatch
contrib module.</td>
</tr>
</tbody>
</table>
<a name="escape-datetime-functions-table"></a>
**Table 8.3. Supported escaped date/time functions**
<table summary="Supported escaped date/time functions" class="CALSTABLE" border="1">
<tr>
<th>function</th>
<th>reported as supported</th>
<th>translation</th>
<th>comments</th>
</tr>
<tbody>
<tr>
<td>curdate()</td>
<td>yes</td>
<td>current_date</td>
<td> </td>
</tr>
<tr>
<td>curtime()</td>
<td>yes</td>
<td>current_time</td>
<td> </td>
</tr>
<tr>
<td>dayname(arg1)</td>
<td>yes</td>
<td>to_char(arg1,'Day')</td>
<td> </td>
</tr>
<tr>
<td>dayofmonth(arg1)</td>
<td>yes</td>
<td>extract(day from arg1)</td>
<td> </td>
</tr>
<tr>
<td>dayofweek(arg1)</td>
<td>yes</td>
<td>extract(dow from arg1)+1</td>
<td>We must add 1 to be in the expected 1-7 range.</td>
</tr>
<tr>
<td>dayofyear(arg1)</td>
<td>yes</td>
<td>extract(doy from arg1)</td>
<td> </td>
</tr>
<tr>
<td>hour(arg1)</td>
<td>yes</td>
<td>extract(hour from arg1)</td>
<td> </td>
</tr>
<tr>
<td>minute(arg1)</td>
<td>yes</td>
<td>extract(minute from arg1)</td>
<td> </td>
</tr>
<tr>
<td>month(arg1)</td>
<td>yes</td>
<td>extract(month from arg1)</td>
<td> </td>
</tr>
<tr>
<td>monthname(arg1)</td>
<td>yes</td>
<td>to_char(arg1,'Month')</td>
<td> </td>
</tr>
<tr>
<td>now()</td>
<td>yes</td>
<td>now()</td>
<td> </td>
</tr>
<tr>
<td>quarter(arg1)</td>
<td>yes</td>
<td>extract(quarter from arg1)</td>
<td> </td>
</tr>
<tr>
<td>second(arg1)</td>
<td>yes</td>
<td>extract(second from arg1)</td>
<td> </td>
</tr>
<tr>
<td>week(arg1)</td>
<td>yes</td>
<td>extract(week from arg1)</td>
<td> </td>
</tr>
<tr>
<td>year(arg1)</td>
<td>yes</td>
<td>extract(year from arg1)</td>
<td> </td>
</tr>
<tr>
<td>timestampadd(argIntervalType,argCount,argTimeStamp)</td>
<td>yes</td>
<td>('(interval according to argIntervalType and
argCount)'+argTimeStamp)</td>
<td>an argIntervalType value of SQL_TSI_FRAC_SECOND
is not implemented since backend does not support it</td>
</tr>
<tr>
<td>timestampdiff(argIntervalType,argTimeStamp1,argTimeStamp2)</td>
<td>not</td>
<td>extract((interval according to argIntervalType) from
argTimeStamp2-argTimeStamp1 )</td>
<td>only an argIntervalType value of SQL_TSI_FRAC_SECOND, SQL_TSI_FRAC_MINUTE, SQL_TSI_FRAC_HOUR
or SQL_TSI_FRAC_DAY is supported </td>
</tr>
</tbody>
</table>
<a name="escape-misc-functions-table"></a>
**Table 8.4. Supported escaped misc functions**
<table summary="Supported escaped misc functions" class="CALSTABLE" border="1">
<tr>
<th>function</th>
<th>reported as supported</th>
<th>translation</th>
<th>comments</th>
</tr>
<tbody>
<tr>
<td>database()</td>
<td>yes</td>
<td>current_database()</td>
<td>Only reported as supported by 7.3 and above servers.</td>
</tr>
<tr>
<td>ifnull(arg1,arg2)</td>
<td>yes</td>
<td>coalesce(arg1,arg2)</td>
<td> </td>
</tr>
<tr>
<td>user()</td>
<td>yes</td>
<td>user</td>
<td> </td>
</tr>
</tbody>
</table>
|
