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From Alan Burlison <Alan.Burli...@sun.com>
Subject Re: any feedback on this?
Date Tue, 24 Jun 2008 09:16:24 GMT
Knut Anders Hatlen wrote:

> Both of the above queries would normally use the index on upper_col, if
> such an index is present.


I've hit another snag though - I want the index to be unique and I was 
going to keep the case-converted column up-to-date using 'after' 
triggers.  However you can't use after triggers to populate a column 
which has a unique index.  If you use a multi-row insert, the triggers 
don't fire until after *all* the rows have been inserted, which results 
in multiple nulls in the case-converted columns, which in turn cause an 
error because an unique index can't contain multiple nulls.

Bah.  Looks like I'm going to have to switch to MySQL after all. :-(

Alan Burlison

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