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drop table if exists t1;
CREATE TABLE t1 SELECT _utf8'test' as c1, _utf8'ัะตัั' as c2;
SHOW CREATE TABLE t1;
Table Create Table
t1 CREATE TABLE `t1` (
`c1` varchar(4) CHARACTER SET utf8mb3 COLLATE utf8mb3_uca1400_ai_ci NOT NULL,
`c2` varchar(4) CHARACTER SET utf8mb3 COLLATE utf8mb3_uca1400_ai_ci NOT NULL
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
DELETE FROM t1;
ALTER TABLE t1 ADD c3 CHAR(4) CHARACTER SET utf8;
SHOW CREATE TABLE t1;
Table Create Table
t1 CREATE TABLE `t1` (
`c1` varchar(4) CHARACTER SET utf8mb3 COLLATE utf8mb3_uca1400_ai_ci NOT NULL,
`c2` varchar(4) CHARACTER SET utf8mb3 COLLATE utf8mb3_uca1400_ai_ci NOT NULL,
`c3` char(4) CHARACTER SET utf8mb3 COLLATE utf8mb3_uca1400_ai_ci DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
INSERT IGNORE INTO t1 VALUES ('aaaabbbbccccdddd','aaaabbbbccccdddd','aaaabbbbccccdddd');
Warnings:
Warning 1265 Data truncated for column 'c1' at row 1
Warning 1265 Data truncated for column 'c2' at row 1
Warning 1265 Data truncated for column 'c3' at row 1
SELECT * FROM t1;
c1 c2 c3
aaaa aaaa aaaa
DROP TABLE t1;
CREATE TABLE t1 (a CHAR(4) CHARACTER SET utf8, KEY key_a(a(3)));
SHOW CREATE TABLE t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` char(4) CHARACTER SET utf8mb3 COLLATE utf8mb3_uca1400_ai_ci DEFAULT NULL,
KEY `key_a` (`a`(3))
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
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 key_a 1 a A NULL 3 NULL YES BTREE NO
ALTER TABLE t1 CHANGE a a CHAR(4);
SHOW CREATE TABLE t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` char(4) DEFAULT NULL,
KEY `key_a` (`a`(3))
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
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 key_a 1 a A NULL 3 NULL YES BTREE NO
ALTER TABLE t1 CHANGE a a CHAR(4) CHARACTER SET utf8;
SHOW CREATE TABLE t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` char(4) CHARACTER SET utf8mb3 COLLATE utf8mb3_uca1400_ai_ci DEFAULT NULL,
KEY `key_a` (`a`(3))
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
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 key_a 1 a A NULL 3 NULL YES BTREE NO
DROP TABLE t1;
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