1.æ·»å PRIMARY KEYï¼ä¸»é®ç´¢å¼ï¼
mysql>ALTER TABLE `table_name` ADD PRIMARY KEY ( `column` )
2.æ·»å UNIQUE(å¯ä¸ç´¢å¼)
mysql>ALTER TABLE `table_name` ADD UNIQUE (
`column`
)
3.æ·»å INDEX(æ®éç´¢å¼)
mysql>ALTER TABLE `table_name` ADD INDEX index_name ( `column` )
4.æ·»å FULLTEXT(å
¨æç´¢å¼)
mysql>ALTER TABLE `table_name` ADD FULLTEXT ( `column`)
5.æ·»å å¤åç´¢å¼
mysql>ALTER TABLE `table_name` ADD INDEX index_name ( `column1`, `column2`, `column3` )
ä¸é¢æ¯æ´å 详ç»çæ¹æ³
MySQLä¸å¯ä»¥ä½¿ç¨alter tableè¿ä¸ªSQLè¯å¥æ¥ä¸ºè¡¨ä¸çå段添å ç´¢å¼ã
使ç¨alter tableè¯å¥æ¥ä¸ºè¡¨ä¸çå段添å ç´¢å¼çåºæ¬è¯æ³æ¯ï¼
ALTER TABLE <表å> ADD INDEX (<å段>);
æ们æ¥å°è¯ä¸ºtestä¸t_nameå段添å ä¸ä¸ªç´¢å¼ã
mysql> alter table test add index(t_name);
Query OK, 0 rows affected (0.17 sec)
Records: 0 Duplicates: 0 Warnings: 0
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mysql> describe test;
+------------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------+-------------+------+-----+---------+-------+
| t_id | int(11) | YES | | NULL | |
| t_name | varchar(50) | NO | MUL | NULL | |
| t_password | char(32) | YES | | NULL | |
| t_birth | date | YES | | NULL | |
+------------+-------------+------+-----+---------+-------+
4 rows in set (0.00 sec)
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