Re: M:M table conditional delete for parents - Mailing list pgsql-general

From Kenneth Downs
Subject Re: M:M table conditional delete for parents
Date
Msg-id 45ED7115.3000506@secdat.com
Whole thread Raw
In response to M:M table conditional delete for parents  (MargaretGillon@chromalloy.com)
Responses Re: M:M table conditional delete for parents  (MargaretGillon@chromalloy.com)
List pgsql-general
MargaretGillon@chromalloy.com wrote:

Postgresql 8.1.4 on Redhat 9

I have a table which stores M:M relationships. I can't put foreign keys to the parents of this table because the relationships being stored go to several tables. This was done so that only two fields have to be searched in order for all relationships to be found for an item. For an oem number there might be 50 to 100 relationships and 40 different tables having to do with materials, locations, revisions, specifications, customer, etc. that might be referenced.

Have you considered creating real cross-reference tables (aka M:M) between all pairs of tables, and then having a view that UNIONs them together?

This way you don't have to re-invent the foreign key to get it all working.



-- 
Kenneth Downs
Secure Data Software, Inc.
www.secdat.com / www.andromeda-project.org
Office: 631-689-7200   Cell: 631-379-0010

::Think you may have a problem with programming? Ask yourself this 
::question: do you worry about how to throw away a garbage can?

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