mysql给一张表新增字段，并设置该字段为外键 - jacunjpg

mysql给一张表新增字段，并设置该字段为外键

首先给usercategory表新增libraryid字段：

alter table usercategory add libraryid varchar(50)

 修改picturelibrary表的libraryid字段为表usercategory的外键

alter table usercategory add constraint libraryid foreign key(libraryid) references picturelibrary(libraryid)