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MySQL之alter语句用法总结_MySQL

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Jun 01, 2016 pm 01:42 PM

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bitsCN.com
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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