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Homephp教程php手册用sql命令修改数据表中的一个字段为非空(not null)的语句

用sql命令修改数据表中的一个字段为非空(not null)的语句

Jun 13, 2016 pm 12:15 PM
alterNOTnullsqltableforReviseOrderFielddata sheetuseofstatementnon empty



ALTER TABLE table1 ALTER COLUMN [name] varchar(60) NULL;

table1 表名 
name 字段名 为什么加上[],因为name是sql关键字会冲突出现错误,这样以防万一。

如果name字段已经创建了索引,如果需要修改的话,必须先删除索引才能正确的进行。

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