How many FK is too many FK ?

Hi gurus,
In our transaction tables, should I create FK for every column to refers to a reference table ? will it degrade performance ?
(e.g : if I have 10 columns in a transaction table as FK, is it too many ?)
Thank you for your help,
xtanto

It depends upon your business rules and application logic. Foreign key is to impose referential integrity between tables (parent/master and child/detail).
To answer whether having 10 columns in a transaction table as FK is subjective, but its true that there are overheads involved in constraints.
You compare and test the performance with and without FKs and see which one would suits you better.
Oracle® Database Application Developer's Guide - Fundamentals, Chapter 6 - Maintaining Data Integrity in Application Development
http://download-east.oracle.com/docs/cd/B19306_01/appdev.102/b14251/adfns_constraints.htm

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