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528 lines
20 KiB
Text
528 lines
20 KiB
Text
#
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# MDEV-7317: Make an index ignorable to the optimizer
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#
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# Test of ALTER INDEX syntax.
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CREATE TABLE t1 ( a INT, KEY (a) );
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SHOW KEYS FROM t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
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t1 1 a 1 a A NULL NULL NULL YES BTREE NO
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ALTER TABLE t1 ALTER INDEX a IGNORED;
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SHOW KEYS FROM t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
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t1 1 a 1 a A NULL NULL NULL YES BTREE YES
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ALTER TABLE t1 ALTER INDEX a NOT IGNORED;
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SHOW KEYS FROM t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
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t1 1 a 1 a A NULL NULL NULL YES BTREE NO
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DROP TABLE t1;
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# Test of CREATE INDEX syntax with IGNORED indexes.
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CREATE TABLE t1 ( a INT, b INT );
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CREATE INDEX a_ignorable ON t1(a) IGNORED;
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CREATE INDEX b_not_ignorable ON t1(a) NOT IGNORED;
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Warnings:
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Note 1831 Duplicate index `b_not_ignorable`. This is deprecated and will be disallowed in a future release
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CREATE INDEX a_b_ignorable ON t1(a, b) IGNORED;
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SHOW INDEXES FROM t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
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t1 1 a_ignorable 1 a A NULL NULL NULL YES BTREE YES
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t1 1 b_not_ignorable 1 a A NULL NULL NULL YES BTREE NO
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t1 1 a_b_ignorable 1 a A NULL NULL NULL YES BTREE YES
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t1 1 a_b_ignorable 2 b A NULL NULL NULL YES BTREE YES
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DROP TABLE t1;
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# Test that IGNORED indexes are not used.
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CREATE TABLE t1 ( a INT, KEY (a) );
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CREATE TABLE t2 ( a INT, KEY (a) IGNORED );
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INSERT INTO t1 VALUES (1), (2), (3), (4), (5);
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INSERT INTO t2 SELECT * FROM t1;
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ANALYZE TABLE t1, t2;
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Table Op Msg_type Msg_text
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test.t1 analyze status Engine-independent statistics collected
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test.t1 analyze status OK
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test.t2 analyze status Engine-independent statistics collected
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test.t2 analyze status Table is already up to date
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EXPLAIN SELECT a FROM t1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL a 5 NULL 5 Using index
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ALTER TABLE t1 ALTER INDEX a IGNORED;
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EXPLAIN SELECT a FROM t1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 5
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ALTER TABLE t1 ALTER INDEX a NOT IGNORED;
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EXPLAIN SELECT a FROM t1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL a 5 NULL 5 Using index
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EXPLAIN SELECT a FROM t2;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t2 ALL NULL NULL NULL NULL 5
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ALTER TABLE t2 ALTER INDEX a NOT IGNORED;
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EXPLAIN SELECT a FROM t2;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t2 index NULL a 5 NULL 5 Using index
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DROP TABLE t1, t2;
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# Test that renaming an index does not change ignorability and vice versa.
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CREATE TABLE t1 (
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a INT, INDEX (a),
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b INT, INDEX (b) IGNORED
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);
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SHOW INDEXES FROM t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
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t1 1 a 1 a A NULL NULL NULL YES BTREE NO
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t1 1 b 1 b A NULL NULL NULL YES BTREE YES
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ALTER TABLE t1 RENAME INDEX a TO a1;
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ALTER TABLE t1 RENAME INDEX b TO b1;
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SHOW INDEXES FROM t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
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t1 1 a1 1 a A NULL NULL NULL YES BTREE NO
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t1 1 b1 1 b A NULL NULL NULL YES BTREE YES
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ALTER TABLE t1 ALTER INDEX a1 IGNORED;
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ALTER TABLE t1 ALTER INDEX b1 NOT IGNORED;
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SHOW INDEXES FROM t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
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t1 1 a1 1 a A NULL NULL NULL YES BTREE YES
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t1 1 b1 1 b A NULL NULL NULL YES BTREE NO
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DROP TABLE t1;
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# Test of SHOW CREATE TABLE.
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CREATE TABLE t1 (
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a INT,
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b INT,
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c INT,
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INDEX (a) NOT IGNORED,
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INDEX (b) IGNORED,
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INDEX (c)
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);
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SHOW CREATE TABLE t1;
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Table Create Table
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t1 CREATE TABLE `t1` (
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`a` int(11) DEFAULT NULL,
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`b` int(11) DEFAULT NULL,
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`c` int(11) DEFAULT NULL,
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KEY `a` (`a`),
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KEY `b` (`b`) IGNORED,
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KEY `c` (`c`)
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) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
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DROP TABLE t1;
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# Test that primary key indexes can't be made ignorable.
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CREATE TABLE t1 ( a INT, PRIMARY KEY (a) IGNORED );
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ERROR HY000: A primary key cannot be marked as IGNORE
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CREATE TABLE t1 ( a INT PRIMARY KEY IGNORED );
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ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'IGNORED )' at line 1
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CREATE TABLE t1 ( a INT KEY IGNORED );
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ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'IGNORED )' at line 1
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ALTER TABLE t1 ALTER INDEX PRIMARY IGNORED;
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ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'PRIMARY IGNORED' at line 1
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CREATE TABLE t1(a INT NOT NULL);
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ALTER TABLE t1 ADD PRIMARY KEY (a) IGNORED;
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ERROR HY000: A primary key cannot be marked as IGNORE
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DROP TABLE t1;
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CREATE TABLE t1 (
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a INT, KEY (a),
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b INT, KEY (b) IGNORED
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);
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ALTER TABLE t1 RENAME INDEX no_such_index TO x;
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ERROR 42000: Key 'no_such_index' doesn't exist in table 't1'
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ALTER TABLE t1 ALTER INDEX no_such_index IGNORED;
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ERROR 42000: Key 'no_such_index' doesn't exist in table 't1'
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DROP TABLE t1;
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CREATE TABLE t1 (
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a INT, KEY (a),
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b INT, KEY (b) IGNORED
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);
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ALTER TABLE t1 RENAME INDEX no_such_index TO x;
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ERROR 42000: Key 'no_such_index' doesn't exist in table 't1'
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ALTER TABLE t1 ALTER INDEX no_such_index IGNORED;
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ERROR 42000: Key 'no_such_index' doesn't exist in table 't1'
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#
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# Repeated alter actions. Should work.
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#
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ALTER TABLE t1 ALTER INDEX a IGNORED, ALTER INDEX a NOT IGNORED;
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SHOW INDEXES FROM t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
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t1 1 a 1 a A NULL NULL NULL YES BTREE NO
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t1 1 b 1 b A NULL NULL NULL YES BTREE YES
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ALTER TABLE t1 ALTER INDEX a NOT IGNORED, ALTER INDEX b IGNORED;
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SHOW INDEXES FROM t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
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t1 1 a 1 a A NULL NULL NULL YES BTREE NO
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t1 1 b 1 b A NULL NULL NULL YES BTREE YES
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#
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# Various combinations of RENAME INDEX and ALTER INDEX ... IGNORED.
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#
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ALTER TABLE t1 RENAME INDEX a TO x, RENAME INDEX x TO a;
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ERROR 42000: Key 'x' doesn't exist in table 't1'
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ALTER TABLE t1 RENAME INDEX a TO x, ALTER INDEX x IGNORED;
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ERROR 42000: Key 'x' doesn't exist in table 't1'
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ALTER TABLE t1 RENAME INDEX a TO x, ALTER INDEX a NOT IGNORED;
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ERROR 42000: Key 'a' doesn't exist in table 't1'
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ALTER TABLE t1 ALTER INDEX a NOT IGNORED, RENAME INDEX a TO x;
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ERROR 42000: Key 'a' doesn't exist in table 't1'
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#
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# Various algorithms and their effects.
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#
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INSERT INTO t1 VALUES (1, 1), (2, 2), (3, 3);
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ANALYZE TABLE t1;
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Table Op Msg_type Msg_text
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test.t1 analyze status Engine-independent statistics collected
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test.t1 analyze status OK
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ALTER TABLE t1 ALTER INDEX a IGNORED, ALGORITHM = COPY;
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affected rows: 3
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info: Records: 3 Duplicates: 0 Warnings: 0
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ANALYZE TABLE t1;
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Table Op Msg_type Msg_text
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test.t1 analyze status Engine-independent statistics collected
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test.t1 analyze status OK
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SHOW INDEXES FROM t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
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t1 1 a 1 a A 3 NULL NULL YES BTREE YES
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t1 1 b 1 b A 3 NULL NULL YES BTREE YES
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ALTER TABLE t1 ALTER INDEX a NOT IGNORED, ALGORITHM = INPLACE;
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affected rows: 0
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info: Records: 0 Duplicates: 0 Warnings: 0
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ANALYZE TABLE t1;
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Table Op Msg_type Msg_text
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test.t1 analyze status Engine-independent statistics collected
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test.t1 analyze status Table is already up to date
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SHOW INDEXES FROM t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
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t1 1 a 1 a A 3 NULL NULL YES BTREE NO
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t1 1 b 1 b A 3 NULL NULL YES BTREE YES
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ALTER TABLE t1 ALTER INDEX a IGNORED, ALGORITHM = DEFAULT;
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affected rows: 0
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info: Records: 0 Duplicates: 0 Warnings: 0
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ANALYZE TABLE t1;
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Table Op Msg_type Msg_text
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test.t1 analyze status Engine-independent statistics collected
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test.t1 analyze status Table is already up to date
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SHOW INDEXES FROM t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
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t1 1 a 1 a A 3 NULL NULL YES BTREE YES
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t1 1 b 1 b A 3 NULL NULL YES BTREE YES
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ALTER TABLE t1 ALTER INDEX a NOT IGNORED;
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affected rows: 0
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info: Records: 0 Duplicates: 0 Warnings: 0
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ANALYZE TABLE t1;
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Table Op Msg_type Msg_text
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test.t1 analyze status Engine-independent statistics collected
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test.t1 analyze status Table is already up to date
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SHOW INDEXES FROM t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
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t1 1 a 1 a A 3 NULL NULL YES BTREE NO
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t1 1 b 1 b A 3 NULL NULL YES BTREE YES
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ALTER TABLE t1 ADD INDEX ab(a, b), ALTER INDEX ab IGNORED;
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ERROR 42000: Key 'ab' doesn't exist in table 't1'
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DROP TABLE t1;
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#
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# The first NOT NULL UNIQUE index may of course be IGNORED if it is
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# not promoted to a primary key
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#
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CREATE TABLE t1 (
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a INT NOT NULL,
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b INT NOT NULL PRIMARY KEY,
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UNIQUE KEY (a) IGNORED
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);
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SHOW INDEXES FROM t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
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t1 0 PRIMARY 1 b A 0 NULL NULL BTREE NO
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t1 0 a 1 a A 0 NULL NULL BTREE YES
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DROP TABLE t1;
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# The check above applies only to the first NOT NULL UNIQUE index.
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CREATE TABLE t1 (
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a INT NOT NULL,
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b INT NOT NULL,
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UNIQUE KEY (a),
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UNIQUE KEY (b) IGNORED
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);
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SHOW INDEXES FROM t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
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t1 0 a 1 a A 0 NULL NULL BTREE NO
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t1 0 b 1 b A 0 NULL NULL BTREE YES
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DROP TABLE t1;
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CREATE TABLE t1 ( a INT NOT NULL, UNIQUE KEY (a) IGNORED);
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ERROR HY000: A primary key cannot be marked as IGNORE
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CREATE TEMPORARY TABLE t1 ( a INT, KEY (a) IGNORED);
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INSERT INTO t1 VALUES (0), (1), (2), (3);
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SHOW INDEXES FROM t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
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t1 1 a 1 a A NULL NULL NULL YES BTREE YES
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EXPLAIN SELECT a FROM t1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 4
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ALTER TABLE t1 ALTER INDEX a NOT IGNORED;
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EXPLAIN SELECT a FROM t1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL a 5 NULL 4 Using index
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DROP TABLE t1;
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#
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# IGNORED fulltext indexes.
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#
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CREATE TABLE t1 (a VARCHAR(200), b TEXT, FULLTEXT (a,b));
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INSERT INTO t1 VALUES('Some data', 'for full-text search'),("hello","hello world"),("mars","here I come");
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SELECT * FROM t1 WHERE MATCH(a, b) AGAINST ("search");
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a b
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Some data for full-text search
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EXPLAIN SELECT * FROM t1 WHERE MATCH(a, b) AGAINST ("search");
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 fulltext a a 0 1 Using where
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ALTER TABLE t1 ALTER INDEX a IGNORED;
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SELECT * FROM t1 WHERE MATCH(a, b) AGAINST ("search");
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ERROR HY000: Can't find FULLTEXT index matching the column list
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DROP TABLE t1;
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#
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# IGNORED indexes on AUTO_INCREMENT columns.
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#
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CREATE TABLE t1 ( a INT AUTO_INCREMENT, KEY ( a ) );
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INSERT INTO t1 VALUES (), (), ();
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ANALYZE TABLE t1;
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Table Op Msg_type Msg_text
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test.t1 analyze status Engine-independent statistics collected
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test.t1 analyze status OK
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EXPLAIN SELECT a FROM t1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL a 4 NULL 3 Using index
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ALTER TABLE t1 ALTER INDEX a IGNORED;
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SHOW INDEXES FROM t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
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t1 1 a 1 a A 3 NULL NULL BTREE YES
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EXPLAIN SELECT a FROM t1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 3
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DROP TABLE t1;
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#
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# IGNORED spatial indexes
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#
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CREATE TABLE t1 (
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fid INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
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g GEOMETRY NOT NULL,
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SPATIAL KEY key1(g)
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);
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EXPLAIN SELECT fid, AsText(g) FROM t1
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WHERE Within(g, GeomFromText('Polygon((140 140,160 140,160 160,140 160,140 140))'));
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range key1 key1 34 NULL 8 Using where
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ALTER TABLE t1 ALTER INDEX key1 IGNORED;
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SHOW INDEXES FROM t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
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t1 0 PRIMARY 1 fid A 150 NULL NULL BTREE NO
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t1 1 key1 1 g A NULL 32 NULL SPATIAL YES
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EXPLAIN SELECT fid, AsText(g) FROM t1
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WHERE Within(g, GeomFromText('Polygon((140 140,160 140,160 160,140 160,140 140))'));
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 150 Using where
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DROP TABLE t1;
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CREATE TABLE t1 ( a INT GENERATED ALWAYS AS (1), KEY key1(a));
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INSERT INTO t1 VALUES (),(),();
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SHOW INDEXES FROM t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
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t1 1 key1 1 a A NULL NULL NULL YES BTREE NO
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EXPLAIN SELECT a FROM t1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL key1 5 NULL 3 Using index
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ALTER TABLE t1 ALTER INDEX key1 IGNORED;
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SHOW INDEXES FROM t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
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t1 1 key1 1 a A NULL NULL NULL YES BTREE YES
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EXPLAIN SELECT a FROM t1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 3
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DROP TABLE t1;
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#
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# Partitioning on keys with an IGNORED index, IGNORED indexes over
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# partitioned tables.
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#
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CREATE TABLE t1 (
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a CHAR(2) NOT NULL,
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b CHAR(2) NOT NULL,
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c INT(10) UNSIGNED NOT NULL,
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d VARCHAR(255) DEFAULT NULL,
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e VARCHAR(1000) DEFAULT NULL,
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KEY (a) IGNORED,
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KEY (b)
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) PARTITION BY KEY (a) PARTITIONS 20;
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INSERT INTO t1 (a, b, c, d, e) VALUES
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('07', '03', 343, '1', '07_03_343'),
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('01', '04', 343, '2', '01_04_343'),
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('01', '06', 343, '3', '01_06_343'),
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('01', '07', 343, '4', '01_07_343'),
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('01', '08', 343, '5', '01_08_343'),
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('01', '09', 343, '6', '01_09_343'),
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('03', '03', 343, '7', '03_03_343'),
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('03', '06', 343, '8', '03_06_343'),
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('03', '07', 343, '9', '03_07_343'),
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('04', '03', 343, '10', '04_03_343'),
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('04', '06', 343, '11', '04_06_343'),
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('05', '03', 343, '12', '05_03_343'),
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('11', '03', 343, '13', '11_03_343'),
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('11', '04', 343, '14', '11_04_343');
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ANALYZE TABLE t1;
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Table Op Msg_type Msg_text
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test.t1 analyze status Engine-independent statistics collected
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test.t1 analyze status OK
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EXPLAIN SELECT a FROM t1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 14
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EXPLAIN SELECT b FROM t1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL b 8 NULL 14 Using index
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EXPLAIN SELECT * FROM t1 WHERE a = '04';
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 2 Using where
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ALTER TABLE t1 ALTER INDEX a NOT IGNORED;
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EXPLAIN SELECT a FROM t1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL a 8 NULL 14 Using index
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EXPLAIN SELECT * FROM t1 WHERE a = '04';
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ref a a 8 const 2 Using index condition
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ALTER TABLE t1 ALTER INDEX b IGNORED;
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EXPLAIN SELECT b FROM t1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 14
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DROP TABLE t1;
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#
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# Using FORCE INDEX for an IGNORED index
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#
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CREATE TABLE t1(a INT, key k1(a));
|
|
INSERT INTO t1 VALUES (1),(2),(3);
|
|
EXPLAIN SELECT * FROM t1 FORCE INDEX(k1);
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL k1 5 NULL 3 Using index
|
|
ALTER TABLE t1 ALTER INDEX k1 IGNORED;
|
|
SHOW CREATE TABLE t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`a` int(11) DEFAULT NULL,
|
|
KEY `k1` (`a`) IGNORED
|
|
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
|
|
EXPLAIN SELECT * FROM t1 FORCE INDEX(k1);
|
|
ERROR 42000: Key 'k1' doesn't exist in table 't1'
|
|
DROP TABLE t1;
|
|
#
|
|
# MDEV-25075: Ignorable index makes the resulting CREATE TABLE invalid
|
|
#
|
|
CREATE TABLE t1 (a INT, KEY (a));
|
|
ALTER TABLE t1 ALTER INDEX a IGNORED;
|
|
show create table t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`a` int(11) DEFAULT NULL,
|
|
KEY `a` (`a`) IGNORED
|
|
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
|
|
DROP TABLE t1;
|
|
CREATE TABLE t1 ( a INT, KEY (a) IGNORED);
|
|
show create table t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`a` int(11) DEFAULT NULL,
|
|
KEY `a` (`a`) IGNORED
|
|
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
|
|
DROP TABLE t1;
|
|
#
|
|
# Tests to check usage of IGNORED keyword
|
|
#
|
|
CREATE TABLE IGNORED(a INT);
|
|
DROP TABLE IGNORED;
|
|
CREATE TABLE t1(a INT);
|
|
SELECT * FROM t1 IGNORED;
|
|
a
|
|
CREATE FUNCTION f1(a INT) RETURNS INT
|
|
BEGIN
|
|
DECLARE IGNORED INT DEFAULT 0;
|
|
RETURN 0;
|
|
END|
|
|
CREATE FUNCTION f2(a INT) RETURNS INT
|
|
BEGIN
|
|
DECLARE IGNORED INT DEFAULT 0;
|
|
DECLARE x INT DEFAULT 0;
|
|
SET x= IGNORED;
|
|
RETURN 0;
|
|
END|
|
|
DROP TABLE t1;
|
|
DROP FUNCTION f1;
|
|
DROP FUNCTION f2;
|
|
CREATE PROCEDURE test_sp()
|
|
BEGIN
|
|
ignored:
|
|
LOOP
|
|
LEAVE ignored;
|
|
END LOOP;
|
|
END|
|
|
DROP PROCEDURE test_sp;
|
|
CREATE PROCEDURE test_sp()
|
|
BEGIN
|
|
set @@ignored= 1;
|
|
END|
|
|
ERROR HY000: Unknown system variable 'ignored'
|
|
CREATE PROCEDURE proc()
|
|
BEGIN
|
|
SET IGNORED= a+b;
|
|
END |
|
|
ERROR HY000: Unknown system variable 'IGNORED'
|
|
#
|
|
# ALLOWING ALTER KEY syntax in ALTER TABLE
|
|
#
|
|
CREATE TABLE t1 (a INT, KEY (a));
|
|
ALTER TABLE t1 ALTER INDEX a IGNORED;
|
|
SHOW CREATE TABLE t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`a` int(11) DEFAULT NULL,
|
|
KEY `a` (`a`) IGNORED
|
|
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
|
|
DROP TABLE t1;
|
|
CREATE TABLE t1 (a INT, KEY (a));
|
|
ALTER TABLE t1 ALTER KEY a IGNORED;
|
|
SHOW CREATE TABLE t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`a` int(11) DEFAULT NULL,
|
|
KEY `a` (`a`) IGNORED
|
|
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
|
|
DROP TABLE t1;
|
|
#
|
|
# MDEV-25078, part #2: allow IF EXISTS
|
|
#
|
|
create table t1 (a int, b int, c int, key(a), key(b), key(c));
|
|
alter table t1 alter key if exists no_such_key ignored;
|
|
Warnings:
|
|
Note 1176 Key 'no_such_key' doesn't exist in table 't1'
|
|
alter table t1 alter key if exists a ignored;
|
|
show create table t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`a` int(11) DEFAULT NULL,
|
|
`b` int(11) DEFAULT NULL,
|
|
`c` int(11) DEFAULT NULL,
|
|
KEY `a` (`a`) IGNORED,
|
|
KEY `b` (`b`),
|
|
KEY `c` (`c`)
|
|
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
|
|
alter table t1
|
|
alter key if exists no_such_key ignored,
|
|
alter key if exists c ignored ;
|
|
Warnings:
|
|
Note 1176 Key 'no_such_key' doesn't exist in table 't1'
|
|
show create table t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`a` int(11) DEFAULT NULL,
|
|
`b` int(11) DEFAULT NULL,
|
|
`c` int(11) DEFAULT NULL,
|
|
KEY `a` (`a`) IGNORED,
|
|
KEY `b` (`b`),
|
|
KEY `c` (`c`) IGNORED
|
|
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
|
|
alter table t1
|
|
alter key if exists no_such_key not ignored,
|
|
alter key if exists c not ignored ;
|
|
Warnings:
|
|
Note 1176 Key 'no_such_key' doesn't exist in table 't1'
|
|
show create table t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`a` int(11) DEFAULT NULL,
|
|
`b` int(11) DEFAULT NULL,
|
|
`c` int(11) DEFAULT NULL,
|
|
KEY `a` (`a`) IGNORED,
|
|
KEY `b` (`b`),
|
|
KEY `c` (`c`)
|
|
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
|
|
drop table t1;
|