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|
DROP TABLE IF EXISTS `ｱｱｱ`;
DROP TABLE IF EXISTS `ｲｲｲ`;
DROP TABLE IF EXISTS `あああ`;
DROP TABLE IF EXISTS `いいい`;
DROP TABLE IF EXISTS `龖龖龖`;
DROP TABLE IF EXISTS `龗龗龗`;
SET NAMES utf8;
SET character_set_database = utf8;
CREATE TABLE `ｱｱｱ`(`ｷｷｷ` char(5)) DEFAULT CHARSET = utf8 engine=INNODB;
CREATE TABLE `ｲｲｲ`(`ｹｹｹ` char(5)) DEFAULT CHARSET = utf8 engine=INNODB;
CREATE TABLE `あああ`(`ききき` char(5)) DEFAULT CHARSET = utf8 engine=INNODB;
CREATE TABLE `いいい`(`けけけ` char(5)) DEFAULT CHARSET = utf8 engine=INNODB;
CREATE TABLE `龖龖龖`(`丂丂丂` char(5)) DEFAULT CHARSET = utf8 engine=INNODB;
CREATE TABLE `龗龗龗`(`乚乚乚` char(5)) DEFAULT CHARSET = utf8 engine=INNODB;
INSERT INTO `ｱｱｱ` VALUES ('ｱｱｱｱｱ'),('ｲｲｲｲｲ'),('ｳｳｳｳｳ');
INSERT INTO `あああ` VALUES ('あああああ'),('いいいいい'),('ううううう');
INSERT INTO `龖龖龖` VALUES ('丂丂丂丂丂'),('丄丄丄丄丄'),('丅丅丅丅丅');
ALTER TABLE `ｱｱｱ` ADD `ｶｶｶ` char(1) FIRST;
ALTER TABLE `ｱｱｱ` ADD `ｸｸｸ` char(1) AFTER `ｷｷｷ`;
ALTER TABLE `ｱｱｱ` ADD `ｹｹｹ` char(1);
ALTER TABLE `ｱｱｱ` ADD INDEX (`ｶｶｶ`);
ALTER TABLE `ｱｱｱ` ADD PRIMARY KEY (`ｷｷｷ`);
ALTER TABLE `ｱｱｱ` ADD UNIQUE (`ｸｸｸ`);
ALTER TABLE `ｱｱｱ` CHANGE `ｶｶｶ` `ｶｶ` char(1);
ALTER TABLE `ｱｱｱ` MODIFY `ｷｷｷ` char(6);
SELECT * FROM `ｱｱｱ`;
ｶｶ ｷｷｷ ｸｸｸ ｹｹｹ
NULL ｱｱｱｱｱ NULL NULL
NULL ｲｲｲｲｲ NULL NULL
NULL ｳｳｳｳｳ NULL NULL
DESC `ｱｱｱ`;
Field Type Null Key Default Extra
ｶｶ char(1) YES MUL NULL
ｷｷｷ char(6) NO PRI NULL
ｸｸｸ char(1) YES UNI NULL
ｹｹｹ char(1) YES NULL
SHOW CREATE TABLE `ｱｱｱ`;
Table Create Table
ｱｱｱ CREATE TABLE `ｱｱｱ` (
`ｶｶ` char(1) DEFAULT NULL,
`ｷｷｷ` char(6) NOT NULL,
`ｸｸｸ` char(1) DEFAULT NULL,
`ｹｹｹ` char(1) DEFAULT NULL,
PRIMARY KEY (`ｷｷｷ`),
UNIQUE KEY `ｸｸｸ` (`ｸｸｸ`),
KEY `ｶｶｶ` (`ｶｶ`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_uca1400_ai_ci
ALTER TABLE `ｱｱｱ` DROP INDEX `ｶｶｶ`;
ALTER TABLE `ｱｱｱ` DROP PRIMARY KEY;
ALTER TABLE `ｱｱｱ` DROP INDEX `ｸｸｸ`;
ALTER TABLE `ｱｱｱ` DROP `ｶｶ`;
ALTER TABLE `ｱｱｱ` DROP `ｸｸｸ`;
ALTER TABLE `ｱｱｱ` DROP `ｹｹｹ`;
SELECT * FROM `ｱｱｱ`;
ｷｷｷ
ｱｱｱｱｱ
ｲｲｲｲｲ
ｳｳｳｳｳ
DESC `ｱｱｱ`;
Field Type Null Key Default Extra
ｷｷｷ char(6) NO NULL
SHOW CREATE TABLE `ｱｱｱ`;
Table Create Table
ｱｱｱ CREATE TABLE `ｱｱｱ` (
`ｷｷｷ` char(6) NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_uca1400_ai_ci
ALTER TABLE `あああ` ADD `かかか` char(1) FIRST;
ALTER TABLE `あああ` ADD `くくく` char(1) AFTER `ききき`;
ALTER TABLE `あああ` ADD `けけけ` char(1);
ALTER TABLE `あああ` ADD INDEX (`かかか`);
ALTER TABLE `あああ` ADD PRIMARY KEY (`ききき`);
ALTER TABLE `あああ` ADD UNIQUE (`くくく`);
ALTER TABLE `あああ` CHANGE `かかか` `かか` char(1);
ALTER TABLE `あああ` MODIFY `ききき` char(6);
SELECT * FROM `あああ`;
かか ききき くくく けけけ
NULL あああああ NULL NULL
NULL いいいいい NULL NULL
NULL ううううう NULL NULL
DESC `あああ`;
Field Type Null Key Default Extra
かか char(1) YES MUL NULL
ききき char(6) NO PRI NULL
くくく char(1) YES UNI NULL
けけけ char(1) YES NULL
SHOW CREATE TABLE `あああ`;
Table Create Table
あああ CREATE TABLE `あああ` (
`かか` char(1) DEFAULT NULL,
`ききき` char(6) NOT NULL,
`くくく` char(1) DEFAULT NULL,
`けけけ` char(1) DEFAULT NULL,
PRIMARY KEY (`ききき`),
UNIQUE KEY `くくく` (`くくく`),
KEY `かかか` (`かか`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_uca1400_ai_ci
ALTER TABLE `あああ` DROP INDEX `かかか`;
ALTER TABLE `あああ` DROP PRIMARY KEY;
ALTER TABLE `あああ` DROP INDEX `くくく`;
ALTER TABLE `あああ` DROP `かか`;
ALTER TABLE `あああ` DROP `くくく`;
ALTER TABLE `あああ` DROP `けけけ`;
SELECT * FROM `あああ`;
ききき
あああああ
いいいいい
ううううう
DESC `あああ`;
Field Type Null Key Default Extra
ききき char(6) NO NULL
SHOW CREATE TABLE `あああ`;
Table Create Table
あああ CREATE TABLE `あああ` (
`ききき` char(6) NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_uca1400_ai_ci
ALTER TABLE `龖龖龖` ADD `丄丄丄` char(1) FIRST;
ALTER TABLE `龖龖龖` ADD `丅丅丅` char(1) AFTER `丂丂丂`;
ALTER TABLE `龖龖龖` ADD `乚乚乚` char(1);
ALTER TABLE `龖龖龖` ADD INDEX (`丄丄丄`);
ALTER TABLE `龖龖龖` ADD PRIMARY KEY (`丂丂丂`);
ALTER TABLE `龖龖龖` ADD UNIQUE (`丅丅丅`);
ALTER TABLE `龖龖龖` CHANGE `丄丄丄` `丄丄` char(1);
ALTER TABLE `龖龖龖` MODIFY `丂丂丂` char(6);
SELECT * FROM `龖龖龖`;
丄丄 丂丂丂 丅丅丅 乚乚乚
NULL 丂丂丂丂丂 NULL NULL
NULL 丄丄丄丄丄 NULL NULL
NULL 丅丅丅丅丅 NULL NULL
DESC `龖龖龖`;
Field Type Null Key Default Extra
丄丄 char(1) YES MUL NULL
丂丂丂 char(6) NO PRI NULL
丅丅丅 char(1) YES UNI NULL
乚乚乚 char(1) YES NULL
SHOW CREATE TABLE `龖龖龖`;
Table Create Table
龖龖龖 CREATE TABLE `龖龖龖` (
`丄丄` char(1) DEFAULT NULL,
`丂丂丂` char(6) NOT NULL,
`丅丅丅` char(1) DEFAULT NULL,
`乚乚乚` char(1) DEFAULT NULL,
PRIMARY KEY (`丂丂丂`),
UNIQUE KEY `丅丅丅` (`丅丅丅`),
KEY `丄丄丄` (`丄丄`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_uca1400_ai_ci
ALTER TABLE `龖龖龖` DROP INDEX `丄丄丄`;
ALTER TABLE `龖龖龖` DROP PRIMARY KEY;
ALTER TABLE `龖龖龖` DROP INDEX `丅丅丅`;
ALTER TABLE `龖龖龖` DROP `丄丄`;
ALTER TABLE `龖龖龖` DROP `丅丅丅`;
ALTER TABLE `龖龖龖` DROP `乚乚乚`;
SELECT * FROM `龖龖龖`;
丂丂丂
丂丂丂丂丂
丄丄丄丄丄
丅丅丅丅丅
DESC `龖龖龖`;
Field Type Null Key Default Extra
丂丂丂 char(6) NO NULL
SHOW CREATE TABLE `龖龖龖`;
Table Create Table
龖龖龖 CREATE TABLE `龖龖龖` (
`丂丂丂` char(6) NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_uca1400_ai_ci
DROP TABLE `ｱｱｱ`;
DROP TABLE `ｲｲｲ`;
DROP TABLE `あああ`;
DROP TABLE `いいい`;
DROP TABLE `龖龖龖`;
DROP TABLE `龗龗龗`;
CREATE TABLE `ｱｱｱ`(`ｷｷｷ` char(5)) DEFAULT CHARSET = utf8 engine=MYISAM;
CREATE TABLE `ｲｲｲ`(`ｹｹｹ` char(5)) DEFAULT CHARSET = utf8 engine=MYISAM;
CREATE TABLE `あああ`(`ききき` char(5)) DEFAULT CHARSET = utf8 engine=MYISAM;
CREATE TABLE `いいい`(`けけけ` char(5)) DEFAULT CHARSET = utf8 engine=MYISAM;
CREATE TABLE `龖龖龖`(`丂丂丂` char(5)) DEFAULT CHARSET = utf8 engine=MYISAM;
CREATE TABLE `龗龗龗`(`乚乚乚` char(5)) DEFAULT CHARSET = utf8 engine=MYISAM;
INSERT INTO `ｱｱｱ` VALUES ('ｱｱｱｱｱ'),('ｲｲｲｲｲ'),('ｳｳｳｳｳ');
INSERT INTO `あああ` VALUES ('あああああ'),('いいいいい'),('ううううう');
INSERT INTO `龖龖龖` VALUES ('丂丂丂丂丂'),('丄丄丄丄丄'),('丅丅丅丅丅');
ALTER TABLE `ｱｱｱ` ADD `ｶｶｶ` char(1) FIRST;
ALTER TABLE `ｱｱｱ` ADD `ｸｸｸ` char(1) AFTER `ｷｷｷ`;
ALTER TABLE `ｱｱｱ` ADD `ｹｹｹ` char(1);
ALTER TABLE `ｱｱｱ` ADD INDEX (`ｶｶｶ`);
ALTER TABLE `ｱｱｱ` ADD PRIMARY KEY (`ｷｷｷ`);
ALTER TABLE `ｱｱｱ` ADD UNIQUE (`ｸｸｸ`);
ALTER TABLE `ｱｱｱ` CHANGE `ｶｶｶ` `ｶｶ` char(1);
ALTER TABLE `ｱｱｱ` MODIFY `ｷｷｷ` char(6);
SELECT * FROM `ｱｱｱ`;
ｶｶ ｷｷｷ ｸｸｸ ｹｹｹ
NULL ｱｱｱｱｱ NULL NULL
NULL ｲｲｲｲｲ NULL NULL
NULL ｳｳｳｳｳ NULL NULL
DESC `ｱｱｱ`;
Field Type Null Key Default Extra
ｶｶ char(1) YES MUL NULL
ｷｷｷ char(6) NO PRI NULL
ｸｸｸ char(1) YES UNI NULL
ｹｹｹ char(1) YES NULL
SHOW CREATE TABLE `ｱｱｱ`;
Table Create Table
ｱｱｱ CREATE TABLE `ｱｱｱ` (
`ｶｶ` char(1) DEFAULT NULL,
`ｷｷｷ` char(6) NOT NULL,
`ｸｸｸ` char(1) DEFAULT NULL,
`ｹｹｹ` char(1) DEFAULT NULL,
PRIMARY KEY (`ｷｷｷ`),
UNIQUE KEY `ｸｸｸ` (`ｸｸｸ`),
KEY `ｶｶｶ` (`ｶｶ`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_uca1400_ai_ci
ALTER TABLE `ｱｱｱ` DROP INDEX `ｶｶｶ`;
ALTER TABLE `ｱｱｱ` DROP PRIMARY KEY;
ALTER TABLE `ｱｱｱ` DROP INDEX `ｸｸｸ`;
ALTER TABLE `ｱｱｱ` DROP `ｶｶ`;
ALTER TABLE `ｱｱｱ` DROP `ｸｸｸ`;
ALTER TABLE `ｱｱｱ` DROP `ｹｹｹ`;
SELECT * FROM `ｱｱｱ`;
ｷｷｷ
ｱｱｱｱｱ
ｲｲｲｲｲ
ｳｳｳｳｳ
DESC `ｱｱｱ`;
Field Type Null Key Default Extra
ｷｷｷ char(6) NO NULL
SHOW CREATE TABLE `ｱｱｱ`;
Table Create Table
ｱｱｱ CREATE TABLE `ｱｱｱ` (
`ｷｷｷ` char(6) NOT NULL
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_uca1400_ai_ci
ALTER TABLE `あああ` ADD `かかか` char(1) FIRST;
ALTER TABLE `あああ` ADD `くくく` char(1) AFTER `ききき`;
ALTER TABLE `あああ` ADD `けけけ` char(1);
ALTER TABLE `あああ` ADD INDEX (`かかか`);
ALTER TABLE `あああ` ADD PRIMARY KEY (`ききき`);
ALTER TABLE `あああ` ADD UNIQUE (`くくく`);
ALTER TABLE `あああ` CHANGE `かかか` `かか` char(1);
ALTER TABLE `あああ` MODIFY `ききき` char(6);
SELECT * FROM `あああ`;
かか ききき くくく けけけ
NULL あああああ NULL NULL
NULL いいいいい NULL NULL
NULL ううううう NULL NULL
DESC `あああ`;
Field Type Null Key Default Extra
かか char(1) YES MUL NULL
ききき char(6) NO PRI NULL
くくく char(1) YES UNI NULL
けけけ char(1) YES NULL
SHOW CREATE TABLE `あああ`;
Table Create Table
あああ CREATE TABLE `あああ` (
`かか` char(1) DEFAULT NULL,
`ききき` char(6) NOT NULL,
`くくく` char(1) DEFAULT NULL,
`けけけ` char(1) DEFAULT NULL,
PRIMARY KEY (`ききき`),
UNIQUE KEY `くくく` (`くくく`),
KEY `かかか` (`かか`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_uca1400_ai_ci
ALTER TABLE `あああ` DROP INDEX `かかか`;
ALTER TABLE `あああ` DROP PRIMARY KEY;
ALTER TABLE `あああ` DROP INDEX `くくく`;
ALTER TABLE `あああ` DROP `かか`;
ALTER TABLE `あああ` DROP `くくく`;
ALTER TABLE `あああ` DROP `けけけ`;
SELECT * FROM `あああ`;
ききき
あああああ
いいいいい
ううううう
DESC `あああ`;
Field Type Null Key Default Extra
ききき char(6) NO NULL
SHOW CREATE TABLE `あああ`;
Table Create Table
あああ CREATE TABLE `あああ` (
`ききき` char(6) NOT NULL
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_uca1400_ai_ci
ALTER TABLE `龖龖龖` ADD `丄丄丄` char(1) FIRST;
ALTER TABLE `龖龖龖` ADD `丅丅丅` char(1) AFTER `丂丂丂`;
ALTER TABLE `龖龖龖` ADD `乚乚乚` char(1);
ALTER TABLE `龖龖龖` ADD INDEX (`丄丄丄`);
ALTER TABLE `龖龖龖` ADD PRIMARY KEY (`丂丂丂`);
ALTER TABLE `龖龖龖` ADD UNIQUE (`丅丅丅`);
ALTER TABLE `龖龖龖` CHANGE `丄丄丄` `丄丄` char(1);
ALTER TABLE `龖龖龖` MODIFY `丂丂丂` char(6);
SELECT * FROM `龖龖龖`;
丄丄 丂丂丂 丅丅丅 乚乚乚
NULL 丂丂丂丂丂 NULL NULL
NULL 丄丄丄丄丄 NULL NULL
NULL 丅丅丅丅丅 NULL NULL
DESC `龖龖龖`;
Field Type Null Key Default Extra
丄丄 char(1) YES MUL NULL
丂丂丂 char(6) NO PRI NULL
丅丅丅 char(1) YES UNI NULL
乚乚乚 char(1) YES NULL
SHOW CREATE TABLE `龖龖龖`;
Table Create Table
龖龖龖 CREATE TABLE `龖龖龖` (
`丄丄` char(1) DEFAULT NULL,
`丂丂丂` char(6) NOT NULL,
`丅丅丅` char(1) DEFAULT NULL,
`乚乚乚` char(1) DEFAULT NULL,
PRIMARY KEY (`丂丂丂`),
UNIQUE KEY `丅丅丅` (`丅丅丅`),
KEY `丄丄丄` (`丄丄`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_uca1400_ai_ci
ALTER TABLE `龖龖龖` DROP INDEX `丄丄丄`;
ALTER TABLE `龖龖龖` DROP PRIMARY KEY;
ALTER TABLE `龖龖龖` DROP INDEX `丅丅丅`;
ALTER TABLE `龖龖龖` DROP `丄丄`;
ALTER TABLE `龖龖龖` DROP `丅丅丅`;
ALTER TABLE `龖龖龖` DROP `乚乚乚`;
SELECT * FROM `龖龖龖`;
丂丂丂
丂丂丂丂丂
丄丄丄丄丄
丅丅丅丅丅
DESC `龖龖龖`;
Field Type Null Key Default Extra
丂丂丂 char(6) NO NULL
SHOW CREATE TABLE `龖龖龖`;
Table Create Table
龖龖龖 CREATE TABLE `龖龖龖` (
`丂丂丂` char(6) NOT NULL
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_uca1400_ai_ci
DROP TABLE `ｱｱｱ`;
DROP TABLE `ｲｲｲ`;
DROP TABLE `あああ`;
DROP TABLE `いいい`;
DROP TABLE `龖龖龖`;
DROP TABLE `龗龗龗`;
CREATE TABLE `ｱｱｱ`(`ｷｷｷ` char(5)) DEFAULT CHARSET = utf8 engine=MEMORY;
CREATE TABLE `ｲｲｲ`(`ｹｹｹ` char(5)) DEFAULT CHARSET = utf8 engine=MEMORY;
CREATE TABLE `あああ`(`ききき` char(5)) DEFAULT CHARSET = utf8 engine=MEMORY;
CREATE TABLE `いいい`(`けけけ` char(5)) DEFAULT CHARSET = utf8 engine=MEMORY;
CREATE TABLE `龖龖龖`(`丂丂丂` char(5)) DEFAULT CHARSET = utf8 engine=MEMORY;
CREATE TABLE `龗龗龗`(`乚乚乚` char(5)) DEFAULT CHARSET = utf8 engine=MEMORY;
INSERT INTO `ｱｱｱ` VALUES ('ｱｱｱｱｱ'),('ｲｲｲｲｲ'),('ｳｳｳｳｳ');
INSERT INTO `あああ` VALUES ('あああああ'),('いいいいい'),('ううううう');
INSERT INTO `龖龖龖` VALUES ('丂丂丂丂丂'),('丄丄丄丄丄'),('丅丅丅丅丅');
ALTER TABLE `ｱｱｱ` ADD `ｶｶｶ` char(1) FIRST;
ALTER TABLE `ｱｱｱ` ADD `ｸｸｸ` char(1) AFTER `ｷｷｷ`;
ALTER TABLE `ｱｱｱ` ADD `ｹｹｹ` char(1);
ALTER TABLE `ｱｱｱ` ADD INDEX (`ｶｶｶ`);
ALTER TABLE `ｱｱｱ` ADD PRIMARY KEY (`ｷｷｷ`);
ALTER TABLE `ｱｱｱ` ADD UNIQUE (`ｸｸｸ`);
ALTER TABLE `ｱｱｱ` CHANGE `ｶｶｶ` `ｶｶ` char(1);
ALTER TABLE `ｱｱｱ` MODIFY `ｷｷｷ` char(6);
SELECT * FROM `ｱｱｱ`;
ｶｶ ｷｷｷ ｸｸｸ ｹｹｹ
NULL ｱｱｱｱｱ NULL NULL
NULL ｲｲｲｲｲ NULL NULL
NULL ｳｳｳｳｳ NULL NULL
DESC `ｱｱｱ`;
Field Type Null Key Default Extra
ｶｶ char(1) YES MUL NULL
ｷｷｷ char(6) NO PRI NULL
ｸｸｸ char(1) YES UNI NULL
ｹｹｹ char(1) YES NULL
SHOW CREATE TABLE `ｱｱｱ`;
Table Create Table
ｱｱｱ CREATE TABLE `ｱｱｱ` (
`ｶｶ` char(1) DEFAULT NULL,
`ｷｷｷ` char(6) NOT NULL,
`ｸｸｸ` char(1) DEFAULT NULL,
`ｹｹｹ` char(1) DEFAULT NULL,
PRIMARY KEY (`ｷｷｷ`),
UNIQUE KEY `ｸｸｸ` (`ｸｸｸ`),
KEY `ｶｶｶ` (`ｶｶ`)
) ENGINE=MEMORY DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_uca1400_ai_ci
ALTER TABLE `ｱｱｱ` DROP INDEX `ｶｶｶ`;
ALTER TABLE `ｱｱｱ` DROP PRIMARY KEY;
ALTER TABLE `ｱｱｱ` DROP INDEX `ｸｸｸ`;
ALTER TABLE `ｱｱｱ` DROP `ｶｶ`;
ALTER TABLE `ｱｱｱ` DROP `ｸｸｸ`;
ALTER TABLE `ｱｱｱ` DROP `ｹｹｹ`;
SELECT * FROM `ｱｱｱ`;
ｷｷｷ
ｱｱｱｱｱ
ｲｲｲｲｲ
ｳｳｳｳｳ
DESC `ｱｱｱ`;
Field Type Null Key Default Extra
ｷｷｷ char(6) NO NULL
SHOW CREATE TABLE `ｱｱｱ`;
Table Create Table
ｱｱｱ CREATE TABLE `ｱｱｱ` (
`ｷｷｷ` char(6) NOT NULL
) ENGINE=MEMORY DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_uca1400_ai_ci
ALTER TABLE `あああ` ADD `かかか` char(1) FIRST;
ALTER TABLE `あああ` ADD `くくく` char(1) AFTER `ききき`;
ALTER TABLE `あああ` ADD `けけけ` char(1);
ALTER TABLE `あああ` ADD INDEX (`かかか`);
ALTER TABLE `あああ` ADD PRIMARY KEY (`ききき`);
ALTER TABLE `あああ` ADD UNIQUE (`くくく`);
ALTER TABLE `あああ` CHANGE `かかか` `かか` char(1);
ALTER TABLE `あああ` MODIFY `ききき` char(6);
SELECT * FROM `あああ`;
かか ききき くくく けけけ
NULL あああああ NULL NULL
NULL いいいいい NULL NULL
NULL ううううう NULL NULL
DESC `あああ`;
Field Type Null Key Default Extra
かか char(1) YES MUL NULL
ききき char(6) NO PRI NULL
くくく char(1) YES UNI NULL
けけけ char(1) YES NULL
SHOW CREATE TABLE `あああ`;
Table Create Table
あああ CREATE TABLE `あああ` (
`かか` char(1) DEFAULT NULL,
`ききき` char(6) NOT NULL,
`くくく` char(1) DEFAULT NULL,
`けけけ` char(1) DEFAULT NULL,
PRIMARY KEY (`ききき`),
UNIQUE KEY `くくく` (`くくく`),
KEY `かかか` (`かか`)
) ENGINE=MEMORY DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_uca1400_ai_ci
ALTER TABLE `あああ` DROP INDEX `かかか`;
ALTER TABLE `あああ` DROP PRIMARY KEY;
ALTER TABLE `あああ` DROP INDEX `くくく`;
ALTER TABLE `あああ` DROP `かか`;
ALTER TABLE `あああ` DROP `くくく`;
ALTER TABLE `あああ` DROP `けけけ`;
SELECT * FROM `あああ`;
ききき
あああああ
いいいいい
ううううう
DESC `あああ`;
Field Type Null Key Default Extra
ききき char(6) NO NULL
SHOW CREATE TABLE `あああ`;
Table Create Table
あああ CREATE TABLE `あああ` (
`ききき` char(6) NOT NULL
) ENGINE=MEMORY DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_uca1400_ai_ci
ALTER TABLE `龖龖龖` ADD `丄丄丄` char(1) FIRST;
ALTER TABLE `龖龖龖` ADD `丅丅丅` char(1) AFTER `丂丂丂`;
ALTER TABLE `龖龖龖` ADD `乚乚乚` char(1);
ALTER TABLE `龖龖龖` ADD INDEX (`丄丄丄`);
ALTER TABLE `龖龖龖` ADD PRIMARY KEY (`丂丂丂`);
ALTER TABLE `龖龖龖` ADD UNIQUE (`丅丅丅`);
ALTER TABLE `龖龖龖` CHANGE `丄丄丄` `丄丄` char(1);
ALTER TABLE `龖龖龖` MODIFY `丂丂丂` char(6);
SELECT * FROM `龖龖龖`;
丄丄 丂丂丂 丅丅丅 乚乚乚
NULL 丂丂丂丂丂 NULL NULL
NULL 丄丄丄丄丄 NULL NULL
NULL 丅丅丅丅丅 NULL NULL
DESC `龖龖龖`;
Field Type Null Key Default Extra
丄丄 char(1) YES MUL NULL
丂丂丂 char(6) NO PRI NULL
丅丅丅 char(1) YES UNI NULL
乚乚乚 char(1) YES NULL
SHOW CREATE TABLE `龖龖龖`;
Table Create Table
龖龖龖 CREATE TABLE `龖龖龖` (
`丄丄` char(1) DEFAULT NULL,
`丂丂丂` char(6) NOT NULL,
`丅丅丅` char(1) DEFAULT NULL,
`乚乚乚` char(1) DEFAULT NULL,
PRIMARY KEY (`丂丂丂`),
UNIQUE KEY `丅丅丅` (`丅丅丅`),
KEY `丄丄丄` (`丄丄`)
) ENGINE=MEMORY DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_uca1400_ai_ci
ALTER TABLE `龖龖龖` DROP INDEX `丄丄丄`;
ALTER TABLE `龖龖龖` DROP PRIMARY KEY;
ALTER TABLE `龖龖龖` DROP INDEX `丅丅丅`;
ALTER TABLE `龖龖龖` DROP `丄丄`;
ALTER TABLE `龖龖龖` DROP `丅丅丅`;
ALTER TABLE `龖龖龖` DROP `乚乚乚`;
SELECT * FROM `龖龖龖`;
丂丂丂
丂丂丂丂丂
丄丄丄丄丄
丅丅丅丅丅
DESC `龖龖龖`;
Field Type Null Key Default Extra
丂丂丂 char(6) NO NULL
SHOW CREATE TABLE `龖龖龖`;
Table Create Table
龖龖龖 CREATE TABLE `龖龖龖` (
`丂丂丂` char(6) NOT NULL
) ENGINE=MEMORY DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_uca1400_ai_ci
DROP TABLE `ｱｱｱ`;
DROP TABLE `ｲｲｲ`;
DROP TABLE `あああ`;
DROP TABLE `いいい`;
DROP TABLE `龖龖龖`;
DROP TABLE `龗龗龗`;
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