Informix - Problem description
Problem IT32024 | Status: Closed |
QUERY TAKES LONGER TIME AND OPTIMIZER CHOOSES SEQUENTIAL SCAN INSTEAD OF INDEX PATH AFTER RUNNING UPDATE STATISTICS MEDIUM/HIGH. | |
product: | |
INFORMIX SERVER / 5725A3900 / C10 - IDS 12.10 | |
Problem description: | |
After upgrading from 12.10.FC10 to 12.10.FC13 query is doing sequential scan and taking longer ( 50 sec to 1 min) after running update statistics high/medium. Using index directive query runs in 15-18 secs. | |
Problem Summary: | |
**************************************************************** * USERS AFFECTED: * * Users of Informix Server prior to 12.10.xC15. * **************************************************************** * PROBLEM DESCRIPTION: * * See Error Description * **************************************************************** * RECOMMENDATION: * * Upgrade to Informix Server 12.10.xC15 (when available). * **************************************************************** | |
Local Fix: | |
A possible workaround may be to set the onconfig parameter OPT_SEEK_FACTOR = 0 or 1. OPT_SEEK_FACTOR is set to favor hash joins on 12.10, and the default value is 6 which could be too high in some cases. onmode -wf OPT_SEEK_FACTOR=0 or onmode -wf OPT_SEEK_FACTOR=1 | |
Solution | |
Workaround | |
**************************************************************** * USERS AFFECTED: * * Users of Informix Server prior to 12.10.xC15. * **************************************************************** * PROBLEM DESCRIPTION: * * See Error Description * **************************************************************** * RECOMMENDATION: * * Upgrade to Informix Server 12.10.xC15 (when available). * **************************************************************** | |
Comment | |
Fixed in Informix Server 12.10.xC15. | |
Timestamps | |
Date - problem reported : Date - problem closed : Date - last modified : | 27.02.2020 10.12.2020 10.12.2020 |
Problem solved at the following versions (IBM BugInfos) | |
Problem solved according to the fixlist(s) of the following version(s) |