Re: Slow queries via Ifx Star

Probably the Ifix-Optimizer (!) gets the wrong index. Use "SET EXPLAIN ON" and "SET EXPLAIN OFF" (If you have a 4GL-Program) to enable a protocol of all the sql-statements that are used and the logfile (sqexplain.out) will show you which index Ifix used and how much the costs for this statement are. Sometimes Informix-Optimizer uses the wrong index if you want to select some fields of another index. e.g. You select Field x,y that are part of index-2 even if you have all information for index-1 Ifix uses index-2 and it will be very slow. This is problem is usually machine- or O.S. - or O.S.-Release-Dependent. Try using Ifix 7.30 there is a new command "USE-INDEX" for sql-statements . Have fun ... Thomas Willaert Doris schrieb in Nachricht <726v5r$8n9$1@news.xmission.com>... > > >System : IBM RS6000 390 AIX 3.2.5 Ifx Online 5.05.UC2 > IBM RS6000 58h AIX 3.2.5 Ifx Online 5.05.UC2 > >Our operational database is on system 58h. Our test system is on system 390. >We have a test database which is a parial copy of the operational database >and for some tables we created synonyms to the operational database. These >tables are accessed via Ifx Star. > >We have the following problem : some of the queries that are done with Ifx >Star are terribely slow when we do them starting form our test system. When >we do them on our operational system we get the result immediatly. > >BTW Update statistics is done every night on both systems. > >Does any one know what could cause this problem ? > >Doris Willaert >Suzuki Belgium >sdwilla@suzuki.be >