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SET NAMES latin1;
CREATE TABLE t1 (
word VARCHAR(64),
bar INT(11) default 0,
PRIMARY KEY (word))
ENGINE=MyISAM
CHARSET utf16
COLLATE utf16_general_ci ;
Warnings:
Warning 1681 Integer display width is deprecated and will be removed in a future release.
INSERT INTO t1 (word) VALUES ("aar");
INSERT INTO t1 (word) VALUES ("a");
INSERT INTO t1 (word) VALUES ("aardvar");
INSERT INTO t1 (word) VALUES ("aardvark");
INSERT INTO t1 (word) VALUES ("aardvara");
INSERT INTO t1 (word) VALUES ("aardvarz");
EXPLAIN SELECT * FROM t1 ORDER BY word;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 NULL ALL NULL NULL NULL NULL 6 100.00 Using filesort
Warnings:
Note 1003 /* select#1 */ select `test`.`t1`.`word` AS `word`,`test`.`t1`.`bar` AS `bar` from `test`.`t1` order by `test`.`t1`.`word`
SELECT * FROM t1 ORDER BY word;
word bar
a 0
aar 0
aardvar 0
aardvara 0
aardvark 0
aardvarz 0
EXPLAIN SELECT word FROM t1 ORDER BY word;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 NULL index NULL PRIMARY 258 NULL 6 100.00 Using index
Warnings:
Note 1003 /* select#1 */ select `test`.`t1`.`word` AS `word` from `test`.`t1` order by `test`.`t1`.`word`
SELECT word FROM t1 ORDER by word;
word
a
aar
aardvar
aardvara
aardvark
aardvarz
DROP TABLE t1;
CREATE TABLE t1 (
word VARCHAR(64) ,
PRIMARY KEY (word))
ENGINE=MyISAM
CHARSET utf16
COLLATE utf16_general_ci;
INSERT INTO t1 (word) VALUES ("aar");
INSERT INTO t1 (word) VALUES ("a");
INSERT INTO t1 (word) VALUES ("aardvar");
INSERT INTO t1 (word) VALUES ("aardvark");
INSERT INTO t1 (word) VALUES ("aardvara");
INSERT INTO t1 (word) VALUES ("aardvarz");
EXPLAIN SELECT * FROM t1 ORDER BY WORD;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 NULL index NULL PRIMARY 258 NULL 6 100.00 Using index
Warnings:
Note 1003 /* select#1 */ select `test`.`t1`.`word` AS `word` from `test`.`t1` order by `test`.`t1`.`word`
SELECT * FROM t1 ORDER BY word;
word
a
aar
aardvar
aardvara
aardvark
aardvarz
DROP TABLE t1;
CREATE TABLE t1 (
word TEXT,
bar INT(11) AUTO_INCREMENT,
PRIMARY KEY (bar))
ENGINE=MyISAM
CHARSET utf16
COLLATE utf16_general_ci ;
Warnings:
Warning 1681 Integer display width is deprecated and will be removed in a future release.
INSERT INTO t1 (word) VALUES ("aar");
INSERT INTO t1 (word) VALUES ("a" );
INSERT INTO t1 (word) VALUES ("aardvar");
INSERT INTO t1 (word) VALUES ("aardvark");
INSERT INTO t1 (word) VALUES ("aardvara");
INSERT INTO t1 (word) VALUES ("aardvarz");
EXPLAIN SELECT * FROM t1 ORDER BY word;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 NULL ALL NULL NULL NULL NULL 6 100.00 Using filesort
Warnings:
Note 1003 /* select#1 */ select `test`.`t1`.`word` AS `word`,`test`.`t1`.`bar` AS `bar` from `test`.`t1` order by `test`.`t1`.`word`
SELECT * FROM t1 ORDER BY word;
word bar
a 2
aar 1
aardvar 3
aardvara 5
aardvark 4
aardvarz 6
EXPLAIN SELECT word FROM t1 ORDER BY word;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 NULL ALL NULL NULL NULL NULL 6 100.00 Using filesort
Warnings:
Note 1003 /* select#1 */ select `test`.`t1`.`word` AS `word` from `test`.`t1` order by `test`.`t1`.`word`
SELECT word FROM t1 ORDER BY word;
word
a
aar
aardvar
aardvara
aardvark
aardvarz
DROP TABLE t1;
create table t1 (
a char(10) character set utf16 not null,
index a (a)
) engine=myisam;
insert into t1 values (repeat(0x201f, 10));
insert into t1 values (repeat(0x2020, 10));
insert into t1 values (repeat(0x2021, 10));
explain select hex(a) from t1 order by a;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 NULL index NULL a 40 NULL 3 100.00 Using index
Warnings:
Note 1003 /* select#1 */ select hex(`test`.`t1`.`a`) AS `hex(a)` from `test`.`t1` order by `test`.`t1`.`a`
select hex(a) from t1 order by a;
hex(a)
201F201F201F201F201F201F201F201F201F201F
2020202020202020202020202020202020202020
2021202120212021202120212021202120212021
alter table t1 drop index a;
select hex(a) from t1 order by a;
hex(a)
201F201F201F201F201F201F201F201F201F201F
2020202020202020202020202020202020202020
2021202120212021202120212021202120212021
drop table t1;
SET sql_mode = '';
create table t1 (a varchar(17000) character set utf16);
Warnings:
Note 1246 Converting column 'a' from VARCHAR to TEXT
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` mediumtext CHARACTER SET utf16 COLLATE utf16_general_ci
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci
drop table t1;
SET sql_mode = default;
create table t1 (a varchar(250) character set utf16 primary key) engine=MyISAM;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` varchar(250) CHARACTER SET utf16 COLLATE utf16_general_ci NOT NULL,
PRIMARY KEY (`a`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci
drop table t1;
create table t1 (a varchar(334) character set utf16 primary key) engine=MyISAM;
ERROR 42000: Specified key was too long; max key length is 1000 bytes
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