MySQL之alter语句用法总结_MySQL
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MySQL之alter语句用法总结 1:删除列ALTER TABLE 【表名字】 DROP 【列名称】2:增加列ALTER TABLE 【表名字】 ADD 【列名称】 INT NOT NULL COMMENT '注释说明'3:修改列的类型信息ALTER TABLE 【表名字】 CHANGE 【列名称】【新列名称(这里可以用和原来列同名即可)】 BIGINT NOT NULL COMMENT '注释说明'4:重命名列ALTER TABLE 【表名字】 CHANGE 【列名称】【新列名称】 BIGINT NOT NULL COMMENT '注释说明' 5:重命名表ALTER TABLE 【表名字】 RENAME 【表新名字】6:删除表中主键Alter TABLE 【表名字】 drop primary key7:添加主键ALTER TABLE sj_resource_charges ADD CONSTRAINT PK_SJ_RESOURCE_CHARGES PRIMARY KEY (resid,resfromid)8:添加索引ALTER TABLE sj_resource_charges add index INDEX_NAME (name);9: 添加唯一限制条件索引ALTER TABLE sj_resource_charges add unique emp_name2(cardnumber);10: 删除索引alter table tablename drop index emp_name; 作者 三尺之尚 bitsCN.com

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