BobTheDatabaseBoy wrote:
> i grab quotes now and again for use as footers to e-mail
> here in CubeLand. found this one in the stash:
>
> the logic exercised by the database to maintain referential
> integrity is not free, but if the rdbms does not do
> it, it gets done in the application, where it costs the
> same if not more - just now the application becomes
> "slower" versus the rdbms.
> -- Blair Adamanche/2003
>
> while i certainly agree, i've been looking, without success,
> for some numbers that confirm the assertion. if Mr. A is
> lurking, can you provide a reference?
>
> thx,
> btdb
>
That really doesn't require numbers, just horse sense.
Teh app sits on the client. Why make another network trip to confirm
soemthing that thr DBMS can confirm directly?
Also if more than one row is affected the DBMS can parallelize the effort.
In general the app is single threaded...

What soemtimes happes is that the App verifies check and RI "anyway" or
certain properties ar eenforced on a different plane.
In this case DB2 can be taught to trust the app using NOT ENFORCED
ENABLE QUERY OPTIMIZATION properties for check and RI constraints.

Cheers
Serge
Cheers
Serge

--
Serge Rielau
DB2 SQL Compiler Development
IBM Toronto Lab