#
# MDEV-7317: Make an index ignorable to the optimizer
#
# Test of ALTER INDEX syntax.
CREATE TABLE t1 ( a INT, KEY (a) );
SHOW KEYS FROM t1;
Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment	Index_comment	Ignored
t1	1	a	1	a	A	NULL	NULL	NULL	YES	BTREE			NO
ALTER TABLE t1 ALTER INDEX a IGNORED;
SHOW KEYS FROM t1;
Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment	Index_comment	Ignored
t1	1	a	1	a	A	NULL	NULL	NULL	YES	BTREE			YES
ALTER TABLE t1 ALTER INDEX a NOT IGNORED;
SHOW KEYS FROM t1;
Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment	Index_comment	Ignored
t1	1	a	1	a	A	NULL	NULL	NULL	YES	BTREE			NO
DROP TABLE t1;
# Test of CREATE INDEX syntax with IGNORED indexes.
CREATE TABLE t1 ( a INT, b INT );
CREATE INDEX a_ignorable ON t1(a) IGNORED;
CREATE INDEX b_not_ignorable ON t1(a) NOT IGNORED;
Warnings:
Note	1831	Duplicate index `b_not_ignorable`. This is deprecated and will be disallowed in a future release
CREATE INDEX a_b_ignorable ON t1(a, b) IGNORED;
SHOW INDEXES FROM t1;
Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment	Index_comment	Ignored
t1	1	a_ignorable	1	a	A	NULL	NULL	NULL	YES	BTREE			YES
t1	1	b_not_ignorable	1	a	A	NULL	NULL	NULL	YES	BTREE			NO
t1	1	a_b_ignorable	1	a	A	NULL	NULL	NULL	YES	BTREE			YES
t1	1	a_b_ignorable	2	b	A	NULL	NULL	NULL	YES	BTREE			YES
DROP TABLE t1;
# Test that IGNORED indexes are not used.
CREATE TABLE t1 ( a INT, KEY (a) );
CREATE TABLE t2 ( a INT, KEY (a) IGNORED );
INSERT INTO t1 VALUES (1), (2), (3), (4), (5);
INSERT INTO t2 SELECT * FROM t1;
ANALYZE TABLE t1, t2;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
test.t2	analyze	status	Engine-independent statistics collected
test.t2	analyze	status	Table is already up to date
EXPLAIN SELECT a FROM t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index	NULL	a	5	NULL	5	Using index
ALTER TABLE t1 ALTER INDEX a IGNORED;
EXPLAIN SELECT a FROM t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	5	
ALTER TABLE t1 ALTER INDEX a NOT IGNORED;
EXPLAIN SELECT a FROM t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index	NULL	a	5	NULL	5	Using index
EXPLAIN SELECT a FROM t2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	5	
ALTER TABLE t2 ALTER INDEX a NOT IGNORED;
EXPLAIN SELECT a FROM t2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t2	index	NULL	a	5	NULL	5	Using index
DROP TABLE t1, t2;
# Test that renaming an index does not change ignorability and vice versa.
CREATE TABLE t1 (
a INT, INDEX (a),
b INT, INDEX (b) IGNORED
);
SHOW INDEXES FROM t1;
Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment	Index_comment	Ignored
t1	1	a	1	a	A	NULL	NULL	NULL	YES	BTREE			NO
t1	1	b	1	b	A	NULL	NULL	NULL	YES	BTREE			YES
ALTER TABLE t1 RENAME INDEX a TO a1;
ALTER TABLE t1 RENAME INDEX b TO b1;
SHOW INDEXES FROM t1;
Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment	Index_comment	Ignored
t1	1	a1	1	a	A	NULL	NULL	NULL	YES	BTREE			NO
t1	1	b1	1	b	A	NULL	NULL	NULL	YES	BTREE			YES
ALTER TABLE t1 ALTER INDEX a1 IGNORED;
ALTER TABLE t1 ALTER INDEX b1 NOT IGNORED;
SHOW INDEXES FROM t1;
Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment	Index_comment	Ignored
t1	1	a1	1	a	A	NULL	NULL	NULL	YES	BTREE			YES
t1	1	b1	1	b	A	NULL	NULL	NULL	YES	BTREE			NO
DROP TABLE t1;
# Test of SHOW CREATE TABLE.
CREATE TABLE t1 (
a INT,
b INT,
c INT,
INDEX (a) NOT IGNORED,
INDEX (b) IGNORED,
INDEX (c)
);
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`),
  KEY `b` (`b`) IGNORED,
  KEY `c` (`c`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
DROP TABLE t1;
# Test that primary key indexes can't be made ignorable.
CREATE TABLE t1 ( a INT, PRIMARY KEY (a) IGNORED );
ERROR HY000: A primary key cannot be marked as IGNORE
CREATE TABLE t1 ( a INT PRIMARY KEY IGNORED );
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
CREATE TABLE t1 ( a INT KEY IGNORED );
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
ALTER TABLE t1 ALTER INDEX PRIMARY IGNORED;
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
CREATE TABLE t1(a INT NOT NULL);
ALTER TABLE t1 ADD PRIMARY KEY (a) IGNORED;
ERROR HY000: A primary key cannot be marked as IGNORE
DROP TABLE t1;
CREATE TABLE t1 (
a INT, KEY (a),
b INT, KEY (b) IGNORED
);
ALTER TABLE t1 RENAME INDEX no_such_index TO x;
ERROR 42000: Key 'no_such_index' doesn't exist in table 't1'
ALTER TABLE t1 ALTER INDEX no_such_index IGNORED;
ERROR 42000: Key 'no_such_index' doesn't exist in table 't1'
DROP TABLE t1;
CREATE TABLE t1 (
a INT, KEY (a),
b INT, KEY (b) IGNORED
);
ALTER TABLE t1 RENAME INDEX no_such_index TO x;
ERROR 42000: Key 'no_such_index' doesn't exist in table 't1'
ALTER TABLE t1 ALTER INDEX no_such_index IGNORED;
ERROR 42000: Key 'no_such_index' doesn't exist in table 't1'
#
# Repeated alter actions. Should work.
#
ALTER TABLE t1 ALTER INDEX a IGNORED, ALTER INDEX a NOT IGNORED;
SHOW INDEXES FROM t1;
Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment	Index_comment	Ignored
t1	1	a	1	a	A	NULL	NULL	NULL	YES	BTREE			NO
t1	1	b	1	b	A	NULL	NULL	NULL	YES	BTREE			YES
ALTER TABLE t1 ALTER INDEX a NOT IGNORED, ALTER INDEX b IGNORED;
SHOW INDEXES FROM t1;
Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment	Index_comment	Ignored
t1	1	a	1	a	A	NULL	NULL	NULL	YES	BTREE			NO
t1	1	b	1	b	A	NULL	NULL	NULL	YES	BTREE			YES
#
# Various combinations of RENAME INDEX and ALTER INDEX ... IGNORED.
#
ALTER TABLE t1 RENAME INDEX a TO x, RENAME INDEX x TO a;
ERROR 42000: Key 'x' doesn't exist in table 't1'
ALTER TABLE t1 RENAME INDEX a TO x, ALTER INDEX x IGNORED;
ERROR 42000: Key 'x' doesn't exist in table 't1'
ALTER TABLE t1 RENAME INDEX a TO x, ALTER INDEX a NOT IGNORED;
ERROR 42000: Key 'a' doesn't exist in table 't1'
ALTER TABLE t1 ALTER INDEX a NOT IGNORED, RENAME INDEX a TO x;
ERROR 42000: Key 'a' doesn't exist in table 't1'
#
# Various algorithms and their effects.
#
INSERT INTO t1 VALUES (1, 1), (2, 2), (3, 3);
ANALYZE TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
ALTER TABLE t1 ALTER INDEX a IGNORED, ALGORITHM = COPY;
affected rows: 3
info: Records: 3  Duplicates: 0  Warnings: 0
ANALYZE TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
SHOW INDEXES FROM t1;
Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment	Index_comment	Ignored
t1	1	a	1	a	A	3	NULL	NULL	YES	BTREE			YES
t1	1	b	1	b	A	3	NULL	NULL	YES	BTREE			YES
ALTER TABLE t1 ALTER INDEX a NOT IGNORED, ALGORITHM = INPLACE;
affected rows: 0
info: Records: 0  Duplicates: 0  Warnings: 0
ANALYZE TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	Table is already up to date
SHOW INDEXES FROM t1;
Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment	Index_comment	Ignored
t1	1	a	1	a	A	3	NULL	NULL	YES	BTREE			NO
t1	1	b	1	b	A	3	NULL	NULL	YES	BTREE			YES
ALTER TABLE t1 ALTER INDEX a IGNORED, ALGORITHM = DEFAULT;
affected rows: 0
info: Records: 0  Duplicates: 0  Warnings: 0
ANALYZE TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	Table is already up to date
SHOW INDEXES FROM t1;
Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment	Index_comment	Ignored
t1	1	a	1	a	A	3	NULL	NULL	YES	BTREE			YES
t1	1	b	1	b	A	3	NULL	NULL	YES	BTREE			YES
ALTER TABLE t1 ALTER INDEX a NOT IGNORED;
affected rows: 0
info: Records: 0  Duplicates: 0  Warnings: 0
ANALYZE TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	Table is already up to date
SHOW INDEXES FROM t1;
Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment	Index_comment	Ignored
t1	1	a	1	a	A	3	NULL	NULL	YES	BTREE			NO
t1	1	b	1	b	A	3	NULL	NULL	YES	BTREE			YES
ALTER TABLE t1 ADD INDEX ab(a, b), ALTER INDEX ab IGNORED;
ERROR 42000: Key 'ab' doesn't exist in table 't1'
DROP TABLE t1;
#
# The first NOT NULL UNIQUE index may of course be IGNORED if it is
# not promoted to a primary key
#
CREATE TABLE t1 (
a INT NOT NULL,
b INT NOT NULL PRIMARY KEY,
UNIQUE KEY (a) IGNORED
);
SHOW INDEXES FROM t1;
Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment	Index_comment	Ignored
t1	0	PRIMARY	1	b	A	0	NULL	NULL		BTREE			NO
t1	0	a	1	a	A	0	NULL	NULL		BTREE			YES
DROP TABLE t1;
# The check above applies only to the first NOT NULL UNIQUE index.
CREATE TABLE t1 (
a INT NOT NULL,
b INT NOT NULL,
UNIQUE KEY (a),
UNIQUE KEY (b) IGNORED
);
SHOW INDEXES FROM t1;
Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment	Index_comment	Ignored
t1	0	a	1	a	A	0	NULL	NULL		BTREE			NO
t1	0	b	1	b	A	0	NULL	NULL		BTREE			YES
DROP TABLE t1;
CREATE TABLE t1 ( a INT NOT NULL, UNIQUE KEY (a) IGNORED);
ERROR HY000: A primary key cannot be marked as IGNORE
CREATE TEMPORARY TABLE t1 ( a INT, KEY (a) IGNORED);
INSERT INTO t1 VALUES (0), (1), (2), (3);
SHOW INDEXES FROM t1;
Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment	Index_comment	Ignored
t1	1	a	1	a	A	NULL	NULL	NULL	YES	BTREE			YES
EXPLAIN SELECT a FROM t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	4	
ALTER TABLE t1 ALTER INDEX a NOT IGNORED;
EXPLAIN SELECT a FROM t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index	NULL	a	5	NULL	4	Using index
DROP TABLE t1;
#
# IGNORED fulltext indexes.
#
CREATE TABLE t1 (a VARCHAR(200), b TEXT, FULLTEXT (a,b));
INSERT INTO t1 VALUES('Some data', 'for full-text search');
ANALYZE TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	Warning	Engine-independent statistics are not collected for column 'b'
test.t1	analyze	status	OK
EXPLAIN SELECT * FROM t1 WHERE MATCH(a, b) AGAINST ("collections");
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	fulltext	a	a	0		1	Using where
ALTER TABLE t1 ALTER INDEX a IGNORED;
EXPLAIN SELECT * FROM t1 WHERE MATCH(a, b) AGAINST ("collections");
ERROR HY000: Can't find FULLTEXT index matching the column list
DROP TABLE t1;
#
# IGNORED indexes on AUTO_INCREMENT columns.
#
CREATE TABLE t1 ( a INT AUTO_INCREMENT, KEY ( a ) );
INSERT INTO t1 VALUES (), (), ();
ANALYZE TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
EXPLAIN SELECT a FROM t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index	NULL	a	4	NULL	3	Using index
ALTER TABLE t1 ALTER INDEX a IGNORED;
SHOW INDEXES FROM t1;
Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment	Index_comment	Ignored
t1	1	a	1	a	A	3	NULL	NULL		BTREE			YES
EXPLAIN SELECT a FROM t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	
DROP TABLE t1;
#
# IGNORED spatial indexes
#
CREATE TABLE t1 (
fid INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
g GEOMETRY NOT NULL,
SPATIAL KEY key1(g)
);
EXPLAIN SELECT fid, AsText(g) FROM t1
WHERE Within(g, GeomFromText('Polygon((140 140,160 140,160 160,140 160,140 140))'));
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	range	key1	key1	34	NULL	8	Using where
ALTER TABLE t1 ALTER INDEX key1 IGNORED;
SHOW INDEXES FROM t1;
Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment	Index_comment	Ignored
t1	0	PRIMARY	1	fid	A	150	NULL	NULL		BTREE			NO
t1	1	key1	1	g	A	NULL	32	NULL		SPATIAL			YES
EXPLAIN SELECT fid, AsText(g) FROM t1
WHERE Within(g, GeomFromText('Polygon((140 140,160 140,160 160,140 160,140 140))'));
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	150	Using where
DROP TABLE t1;
CREATE TABLE t1 ( a INT GENERATED ALWAYS AS (1), KEY key1(a));
INSERT INTO t1 VALUES (),(),();
SHOW INDEXES FROM t1;
Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment	Index_comment	Ignored
t1	1	key1	1	a	A	NULL	NULL	NULL	YES	BTREE			NO
EXPLAIN SELECT a FROM t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index	NULL	key1	5	NULL	3	Using index
ALTER TABLE t1 ALTER INDEX key1 IGNORED;
SHOW INDEXES FROM t1;
Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment	Index_comment	Ignored
t1	1	key1	1	a	A	NULL	NULL	NULL	YES	BTREE			YES
EXPLAIN SELECT a FROM t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	
DROP TABLE t1;
#
# Partitioning on keys with an IGNORED index, IGNORED indexes over
# partitioned tables.
#
CREATE TABLE t1 (
a CHAR(2) NOT NULL,
b CHAR(2) NOT NULL,
c INT(10) UNSIGNED NOT NULL,
d VARCHAR(255) DEFAULT NULL,
e VARCHAR(1000) DEFAULT NULL,
KEY (a) IGNORED,
KEY (b)
) PARTITION BY KEY (a) PARTITIONS 20;
INSERT INTO t1 (a, b, c, d, e) VALUES
('07', '03', 343, '1', '07_03_343'),
('01', '04', 343, '2', '01_04_343'),
('01', '06', 343, '3', '01_06_343'),
('01', '07', 343, '4', '01_07_343'),
('01', '08', 343, '5', '01_08_343'),
('01', '09', 343, '6', '01_09_343'),
('03', '03', 343, '7', '03_03_343'),
('03', '06', 343, '8', '03_06_343'),
('03', '07', 343, '9', '03_07_343'),
('04', '03', 343, '10', '04_03_343'),
('04', '06', 343, '11', '04_06_343'),
('05', '03', 343, '12', '05_03_343'),
('11', '03', 343, '13', '11_03_343'),
('11', '04', 343, '14', '11_04_343');
ANALYZE TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
EXPLAIN SELECT a FROM t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	14	
EXPLAIN SELECT b FROM t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index	NULL	b	2	NULL	14	Using index
EXPLAIN SELECT * FROM t1 WHERE a = '04';
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	8	Using where
ALTER TABLE t1 ALTER INDEX a NOT IGNORED;
EXPLAIN SELECT a FROM t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index	NULL	a	2	NULL	14	Using index
EXPLAIN SELECT * FROM t1 WHERE a = '04';
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ref	a	a	2	const	2	Using where
ALTER TABLE t1 ALTER INDEX b IGNORED;
EXPLAIN SELECT b FROM t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	14	
DROP TABLE t1;
#
# Using FORCE INDEX for an IGNORED index
#
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=latin1 COLLATE=latin1_swedish_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=latin1 COLLATE=latin1_swedish_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=latin1 COLLATE=latin1_swedish_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=latin1 COLLATE=latin1_swedish_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=latin1 COLLATE=latin1_swedish_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=latin1 COLLATE=latin1_swedish_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=latin1 COLLATE=latin1_swedish_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=latin1 COLLATE=latin1_swedish_ci
drop table t1;