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在SQL中添加外键约束

更新时间:2022-10-23 23:40:04

请查看以下链接,以获取有关" FOREIGN KEY Constraint "的信息.

http://www.w3schools.com/sql/sql_foreignkey.asp

http://msdn.microsoft.com/en-us/library/ms175464.aspx


,这意味着您的表2没有要由表1引用的主键.
首先将主键分配给要加入的辅助表

问候,
Eduard


在参考表中将Consumer_ID更改为主键


hi i have two tables. when i tried to add a foreign key using this query


alter  table tbl_user_login add constraint fkcid foreign key(fk_Consumer_ID) references tbl_Consumer_details(Consumer_ID)




it shows an error:

There are no primary or candidate keys in the referenced table ''tbl_Consumer_details'' that match the referencing column list in the foreign key ''fkcid''.


help me

thanks in advance

Have a look at below links for information on "FOREIGN KEY Constraint".

http://www.w3schools.com/sql/sql_foreignkey.asp

http://msdn.microsoft.com/en-us/library/ms175464.aspx


this means your table 2 doesn''t have a primary key to be referenced by table 1.

Assign a primary key first to the secondary table you are joining

Regards,
Eduard


Change Consumer_ID as Primary Key in the reference table