Primary Key Foreign Key Tables

21 Oct 2005 1:41 PM

thomson

Hi All,
i do have two table a Master and a Detail which has a primary
key on the Master Table and Foreign key on the Detail Table

How do i insist that when ever there is a entry in the Master table
there should atleast exist one record in the Detail Table. Any sort of
condition can be made

Thanks in advance

thomson

21 Oct 2005 2:02 PM

Gerard

Have a look at BOL "Constraints" and "Foreign key constraints"

HTH
Gerard

21 Oct 2005 3:00 PM

Anith Sen

Circular references are complex in SQL. An easier way is to write a trigger
to check the existance of rows in the referencing table.

--
Anith

21 Oct 2005 3:59 PM

Trey Walpole

This is typically handled best in a client application (e.g., an n-tier
object) as a business rule.

see the following link for some more thoughts on this:
http://expertanswercenter.techtarget.com/eac/knowledgebaseAnswer/0,295199,sid63_gci976558,00.html

thomson wrote:

Show quote

>Hi All,
> i do have two table a Master and a Detail which has a primary
>key on the Master Table and Foreign key on the Detail Table
>
>
>How do i insist that when ever there is a entry in the Master table
>there should atleast exist one record in the Detail Table. Any sort of
>condition can be made
>
>
>Thanks in advance
>
>thomson
>
>
>