[GENERAL] foreign key help

[Dale Sykora]

I am building a database that has about 20 fields in various tables that 
 I would like to constrain to a small group (<=5) of choices.  Rather 
that refer to 20 seperate tables, I would like to refer to 1 table that 
contained category and choice fields.

for example
choices table
category | choice
-----------------
color    | red
color    | green
size     | small
size     | big
shape    | circle
shape    | square
item table
item     |  shape
-----------------
box      |  constrain to choices(choice) where category='shape'

Is there an easy way to do this, or is it better to have many 
choices_category tables?

Thanks,
Dale

---------------------------(end of broadcast)---------------------------
TIP 5: Have you checked our extensive FAQ?
              http://www.postgresql.org/docs/faq