Subject Re: [firebird-support] Re: concatenation faster than AND in WHERE clause?
Author Daniel Rail

At June 20, 2003, 06:27, tomasz007 wrote:
> Before I decide to put 1.5 in the production environment, I'll
> implement some smart mechanism into parts of my app that
> automatically generate where clauses to optionally include the 'or
> trick'. Also will review other slowest queries and will try to
> improve them with this trick.

You might want to test FB 1.5 RC3 first. I've seen some of my queries
increase in speed dramatically(between 2x and 100x). Just to give you
an example, I have a query that returns an aged accounts
receivable(0-30 days, 31-60, etc...), and that query, on FB 1.0, would
take over 10 minutes(because of the amount of data and subqueries),
with FB 1.5 RC3, that's cut down to just over 30 seconds. FB 1.5 has
more improvements other than the optimizer, better memory management,
the sort uses available memory before using the hard-disk, and there's
other improvements for better overall performance. So, before you
start tweaking your queries, give them a test run on FB 1.5, so you
can compare and see which queries you have to tweak for better

Best regards,
Daniel Rail
Senior System Engineer
ACCRA Group Inc. (
ACCRA Med Software Inc. (