Dear Monks,

Please excuse this off topic post but I find that perlmonks.com is the only place where I can get useful and timely feedback on software issues. I am questioning the wisdom of using a foreign key constraint to enforce check constraint like functionality.

I have several tables that I use to "decode" integer values to more readable strings.

Example: I have one table called department which is defined like so.
ID            NUMBER PRIMARY KEY
DEPT_CODE     VARCHAR2(5) 
...

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And I add the foreign key with the alter table command. 
ALTER TABLE DEPARTMENT ADD CONSTRAINT DEPT_NUM_CK_FK
FOREIGN KEY ( DEPT_CODE ) REFERENCES DEPARTMENT_CODES.CODE;

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The DEPARTMENT_CODES table has values like this: 
SEQ   CODE    NAME 
---   -----   -----------------------------
  1   H23R    Human Resources 
  2   1126    R & D
...

[download]
This way when someone try's and enters a code that is not in DEPARTMENT_CODES table they will get a integrity constraint violate.

I was just wondering if any monks have used this type of approach and if using check constraints maybe better. We have about 2000 values in the DEPARTMENT_CODE table.
Thanks for you time :)

In reply to (OT) database design question by Anonymous Monk

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