FW: MATCHES problem

I found similar porblem with 7.12 and 7.13 where using a matches clause we ended up with a sequential scan and found the problem was a tunable parameter. Take a closer look at you explain file a see if it is doing a dynamic hash join. If this is your problem take a look at the OPTCOMPIND tunable parameter. We found if we set it to '0' we had much better luck... Hoe this helps... }---------- }From: Ian Goddard[SMTP:igoddard@netcomuk.co.uk] }Sent: Monday, January 13, 1997 10:31 AM }To: informix-list@rmy.emory.edu }Subject: Re: MATCHES problem } }ACE wrote: }> }> I've encountered a serious error of INFORMIX-ONLINE v. 7.1x, 7.2x }> on following platforms: }> DYNIX/ptx, SCO UNIX, AIX, DEC OSF UNIX, IRIX, Solaris and HP/UX. }> Construction: }> select tabid from systables where tabname matches 'sys*' }> shows with EXPLAIN ON: SEQUENTIAL SCAN }> }> select tabid from systables where tabname[1,3]='sys' }> shows INDEX SCAN }> (Indexes are not used even one use simple 'matches' phrase). }> This error doesn't occur in versions 5.x of ONLINE. }> Think about table with over 2,000,000 records. } }I thought about it. This would mean you have 2,000,000 tables in your }database. Wow! } }Ian }