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DROP TABLE IF EXISTS t1;
CREATE TABLE t1 (a <INT_COLUMN>, <CUSTOM_INDEX>(a)) ENGINE=<STORAGE_ENGINE> <CUSTOM_TABLE_OPTIONS>;
INSERT INTO t1 (a) VALUES (10);
INSERT INTO t1 (a) VALUES
(1),(2),(3),(4),(5),(6),(7),(8),(9),
(21),(22),(23),(24),(25),(26),(27),(28),(29);
EXPLAIN SELECT a FROM t1 ORDER BY a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index NULL a 5 NULL # Using index
SHOW INDEX IN t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment
t1 1 a 1 a # # NULL NULL YES BTREE
ALTER TABLE t1 DISABLE KEYS;
SHOW INDEX IN t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment
t1 1 a 1 a # # NULL NULL YES BTREE disabled
EXPLAIN SELECT a FROM t1 ORDER BY a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 19 Using filesort
INSERT INTO t1 (a) VALUES
(11),(12),(13),(14),(15),(16),(17),(18),(19),(20);
ALTER TABLE t1 ENABLE KEYS;
SHOW INDEX IN t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment
t1 1 a 1 a # # NULL NULL YES BTREE
EXPLAIN SELECT a FROM t1 ORDER BY a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index NULL a 5 NULL # Using index
DROP TABLE t1;
CREATE TABLE t1 (a <INT_COLUMN>, UNIQUE INDEX(a)) ENGINE=<STORAGE_ENGINE> <CUSTOM_TABLE_OPTIONS>;
INSERT INTO t1 (a) VALUES
(1),(2),(3),(4),(5),(6),(7),(8),(9),
(21),(22),(23),(24),(25),(26),(27),(28),(29);
ALTER TABLE t1 DISABLE KEYS;
INSERT INTO t1 (a) VALUES (29);
ERROR 23000: Duplicate entry '29' for key 'a'
# Statement ended with one of expected results (ER_DUP_ENTRY,ER_DUP_KEY).
# If you got a difference in error message, just add it to rdiff file
SHOW INDEX IN t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment
t1 0 a 1 a # # NULL NULL YES BTREE
EXPLAIN SELECT a FROM t1 ORDER BY a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index NULL a 5 NULL # Using index
DROP TABLE t1;
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