Fw: update statistics not recommended!
Posted in 1998
I have been running update statistics on a table with V7.22 ,having seen that costs are increasing tremendously however if you drop index and recreate it with out update stat costs are very low,surprised to see that .... -----Original Message----- From: Neil Truby <ntruby@netcomuk.co.uk> To: informix-list@iiug.org <informix-list@iiug.org> Date: 18 A'ustos 1998 Sal' 07:24 Subject: update statistics not recommended! >My new site has a third-party financial package (Lawsons), running on >v7.13. The underlying DBMS is Informix. The Lawsons help desk has told >me that they recommend that we never run UPDATE STATISTICS, as it will >degrade performance. Their reasoning, allegedly based on empirical >evidence of their users, is that all their SQL is written with where >clauses, and the indexes that exist will be used, which is what is >required. If we run an UPDATE STATS, we might risk unexpected and >undesirable access paths. A caveat is added that, under v7.23, some >customers have experienced benefits from an UPDATE STATISTICS LOW, and >that we might run it, but prepared to remove the statistics so derived >if performance nose-dives. > >Well, sounds like bollocks to me, but does anyone else have any views >or, better still, experience of this software packeage running with >Informix? > >Thanks > >Neil