Re: ATTN: VSATYA RE:Help on Data Integrity Constraints ATTN: VSATYA

"Matt" <none_at_anon.com> wrote:

>VSATYA,
> Foreign key on Status referencing MasterAISTATUS(Code) <---so long as the value is in the column it will be added
> Foreign key on Gender referencing MasterSex_table(Code) <---so long as the value is in the column it will be added
> Foreign key on Designation referencing MasterRoll_table(Desc) <---so long as the value is in the column it will be added

Please don't top-post.

Using a Foreign key constraint on a Gender table is just silly - use a check constraint. You can get skewed indices which can slow things down a lot - same goes for any "binary" value like AISTATUS - check constraint again.

I don't know what my rule of thumb would be, but bascially if you are *_EVER_* going to add to a list of values, use a table and foreign key constraint, but with something like Gender which will *_NEVER_* have any values other than M or F, then use a check constraint.

Paul...

-- 

plinehan __at__ yahoo __dot__ __com__

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When asking database related questions, please give other posters 
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Furthermore, As a courtesy to those who spend 
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do not top post.