以下约束的含义是什么？ [英] what is the meaning of the Constraint in the following.

问题描述

嗨团队，

我有以下SQL信息，我无法理解..

Hi Team,
I have the following SQL information which i am not getting understand..

Constraint_Type     Constraint_Name                  Constraint_Keys
1   FOREIGN KEY   FK_K2ZTECFRDAILY_K2CFRMASTER     CFRMASTERID REFERENCES KAIZEN.dbo.K2CFRMASTER (ID)
3   FOREIGN KEY   FK_K2ZTECFRDAILY_K2FILELOG       FILELOGID REFERENCES KAIZEN.dbo.K2FILELOG (ID)
5   FOREIGN KEY   FK_K2ZTECFRDAILY_K2FILELOGID     FILELOGID REFERENCES KAIZEN.dbo.K2FILELOG (ID)

请有人能解释一下上面的过程。哇这是什么意思？哪个列设置了外键？怎么样？??因为我是新手。请告诉我。



谢谢

Harshal

Please anybody can explain me the above process .What does it mean ?? for which column have set the foreign key?? How it works??.As I am new for this .please let me know.

Thanks
Harshal

推荐答案

阅读：

FOREIGN KEY - 确保一个表中数据的引用完整性与另一个表中的值匹配



http://www.w3schools.com/sql/sql_constraints.asp [ ^ ]

第一个例子



当前表的CFRMASTERID被定义为具有约束名称为FK_K2ZTECFRDAILY_K2CFRMASTER的外键，它存在于K2CIZMASTER KAIZEN数据库表中，列名为ID。

For the first example

CFRMASTERID of current table is defined as foreign key having constraint name as FK_K2ZTECFRDAILY_K2CFRMASTER which is present in K2CFRMASTER Table of KAIZEN database having column name as ID.

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