I agree with the previous posters. Having been a DBA in a previous life, I know it seldomly pays to try to outsmart a database server. People trying to do so either don't know much about SQL and their database, or do really know a lot about SQL, their database and the programming language they use. But if you belonged to the latter category, you wouldn't have asked here. ;-).

Some reasons why the database is faster: 1) SQL isn't a general purpose language; its purpose is to deal with relational data. 2) The database knows the current state - what is in cache, what other queries are being performed, which indices are available, etc. An external program usually doesn't use this information to determine the optimal way of performing the task. 3) No network traffic. 4) Threading.

-- Abigail

In reply to Re: Data Migration Perl style vs. SQL style.... by Abigail
in thread Data Migration Perl style vs. SQL style.... by mr.dunstan

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