On 09/12/06, Nick Meyer <[EMAIL PROTECTED]> wrote:
What is the best way to UPDATE a row only if values are different? We
have a mainframe extract that literally has 100,000 rows and am worried
about the performance of just running INSERTs each night.
Is there a simple comparison command or would you have to nest a SELECT
statement? Thank you,
Nick
You have to check the line first, then compare and update if
neseccary. I've been through that recently, and decided that it was
better to just UPDATE. Of course, I had much less rows than you do.
Maybe you could store an array of changed rows in whatever language
you are programming, then update from that? Or a text file, another
DB, whatever...
Dotan Cohen
http://what-is-what.com/what_is/digg.html
http://dramatherapy.info
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