Re: Re: mysql foreign keys

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> Hi.
>
> Any body got an idea how to use hte foreign keys in mysql innodb tables
> and how whould the change affect the performance of the server?
>
> lets say i have Items table, Clients table, and Sales table
> the Sales table always stores ClientID and ItemID
> but not every client/item is there
> a sale can be deleted without harming the client
> nor the item.
>
> i guess (not sure at all) it should go like :
>
> ALTER TABLE Sales
>  ADD FOREIGN KEY ClientID(ClientID)
>  REFERENCES Clients(ClientID)
>  ON DELETE RESTRICT;
>
> ALTER TABLE Sales
>  ADD FOREIGN KEY ItemID(ItemID)
>  REFERENCES Items(ItemID)
>  ON DELETE RESTRICT;
>
> Am I correct?
>
> thanks.

Take a look here:
http://dev.mysql.com/doc/mysql/en/InnoDB_foreign_key_constraints.html

Regards,
Torsten Roehr

I did the test's and it seems ok, i just want a second opinion,
cause of my lack in experience.
I just want to be sure that's the right and best way of doing it.
btw, the indexes are already set for select joins etc.

Thanks

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