>>Nadya,
>>
>>FK constraints on lookups are every bit as critical. If you use a single overloaded lookup table you need to ensure that you constrain the lookuptype for a given FK into the lookup.
>>
>>>In this question I was more concerned about lookup tables. Of course, for real parent and child we must have triggers in place. I do agree with having them for lookup as well, but want to find out the general practice.
>
>That was originally implemented with very fanky indexes. We changed the indexes, but left the constrains. So, you're right, they don't make much sense now!
>
>Thanks for helping me in realizing that.
I think, we may be better off with the field's rule for these fields instead of the triggers.
If it's not broken, fix it until it is.
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