On Mar 29, 2006, at 12:35 PM, Nico Callewaert wrote:
Because from what I understand, for every foreign key, there is an index defined. So, all these indexes has to be maintained. Is that killing performance ? What's the best practise : defining foreign keys or not ?
If your application is 100% perfect and you never do any manual updates to the DB, then who needs FK's?
Show me that your app is 100% perfect first... which there is no way you can do unless it is a trivial amount of code.
But just defining FK's won't define an index. You have to do that manually else suffer performance. However, if the referenced table is only a few hundred rows or less, there is not much point in an index on that column for that table.
Personally, I live by FKs since I value my data to be correct.
