creating a constraint on the same table

I have a category table with a primary key called cat_id

and another column called parent_id

 

the parent_id must be part of the cat_id column

 

it's alot like a foreign key constraint but I don't know the sql to do it.

any ideas?

 

Is this a novice question or should I try a different list?

Matt Friedman
Spry New Media
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Lead Programmer/Partner
email: matt@sprynewmedia.com
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