Re: Integrity constraint
Date: Tue, 3 Feb 2009 04:43:38 -0800 (PST)
I looke up De Morgans law and accordingly, the English translation is "This claim asserts that A is false and B is false."
This is exactly what I want. I want everything in X that does not exist in Y nor in Z. So, we would only get results coming into the final resultset as:
Give me all the records that exist in X after ensuring the rows with the same id do not exist in Y and Z.
Please elaborate if I am missing a piece in the puzzle.
Thanks for your response.
On Feb 3, 9:17 am, Michael Rauscher <michlm..._at_gmx.de> wrote:
> vm22 wrote:
> > Hi,
> > I have a developer who has written the following code to delete some
> > records:
> > DELETE FROM x
> > WHERE id NOT IN (SELECT id
> > FROM y)
> > AND id NOT IN (SELECT id
> > FROM z);
> > ORA-02292: integrity constraint (Y_FK) violated - child record found
> > When there is already a clause in my delete to state do not delete
> > records that are found in table Y, why do I get the integrity
> > constraint error message?
> Because a corresponding record exists in table Z?
> Hint: De Morgan's laws
Received on Tue Feb 03 2009 - 06:43:38 CST