https://www.cnblogs.com/bk7788/p/6050184.html SQL Server索引 ...
.添加PRIMARY KEY 主鍵索引 alter table table name add primary key column .添加UNIQUE 唯一索引 alter table table name add unique column .添加普通索引 alter table table name add index index name column .添加全文索引 alter tabl ...
2019-05-22 11:22 0 9143 推薦指數:
https://www.cnblogs.com/bk7788/p/6050184.html SQL Server索引 ...
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UNIQUE (`column`)INDEX(普通索引)mysql>ALTER TABLE `t ...
1.索引類型 UNIQUE(唯一索引):不可以出現相同的值,可以有NULL值; INDEX(普通索引):允許出現相同的索引內容; PROMARY KEY(主鍵索引):不允許出現相同的值; fulltext index(全文索引):可以針對值中的某個單詞,但效率確實不敢恭維 ...
1.添加PRIMARY KEY(主鍵索引) mysql>ALTER TABLE `table_name` ADD PRIMARY KEY ( `column` ) 2.添加UNIQUE(唯一索引) mysql>ALTER TABLE `table_name` ADD ...
1.添加PRIMARY KEY(主鍵索引) mysql>ALTER TABLE `table_name` ADD PRIMARY KEY ( `column` ) 2.添加UNIQUE(唯一索引) mysql>ALTER TABLE `table_name` ADD ...
1.添加PRIMARY KEY(主鍵索引) mysql>ALTER TABLE `table_name` ADD PRIMARY KEY ( `column` ) 2.添加UNIQUE(唯一索引) mysql>ALTER TABLE `table_name` ADD UNIQUE ...
1.PRIMARY KEY(主鍵索引) mysql>ALTER TABLE `table_name` ADD PRIMARY KEY ( `column` ) 2.UNIQUE(唯一索引) mysql>ALTER TABLE ...