RE: Best method for search

Good point Charles. Yes, with 6.1 he ought to be able to build a derived
index that matches the function usage.

Prior to 6.1 it would not perform nearly as well as 3 chains from RPG,
unless he takes the step he mentioned of normalizing the formats into a
separate field and building an index over it. Of course, this would mean
adding an insert & update trigger on the original field, to maintain the
normalized field.

All that said, provided the table is not enormous, I'd like him to try the
query as is. Table scan may perform 'well enough', provided a table fits in
main memory and his iSeries model has a fast CPU(s).

Elvis

Celebrating 11-Years of SQL Performance Excellence on IBM i, i5/OS and
OS/400
www.centerfieldtechnology.com


-----Original Message-----
Subject: Re: Best method for search

Elvis,

I'm not sure that counts as "faster than 3 chains from RPG". Given
that the use of REPLACE on the federalIDColumn would cause a full
table scan correct? (Unless you are running v6r1 perhaps?)

Dean,

Given that you're only dealing with a max of 3 records, I doubt any
SQL method is going to be faster.

Charles