Informix - Problem description
Problem IT28485 | Status: Closed |
12.10 OPTIMIZER CALCULATES THE SELECTIVITY OF A SUBQUERY DIFFERENTLY THAN IN 11.50 | |
product: | |
INFORMIX SERVER / 5725A3900 / C10 - IDS 12.10 | |
Problem description: | |
There was a migration project form 11.50 to 12.10. A very specify query was much much slower compared between both server families. Query looks like this: select accountnumber from accounts where accountnumber between ? and ? and accountnumber [ 1 , 16 ] in ( select targetacc [ 1 , 16 ] from int_target_accounts_t ) and ( intraccount1 in ( select targetacc from int_target_accounts_t ) or intraccount2 in ( select targetacc from int_target_accounts_t ) or intraccount3 in ( select targetacc from int_target_accounts_t ) or intraccount4 in ( select targetacc from int_target_accounts_t ) or intraccount5 in ( select targetacc from int_target_accounts_t ) ) simple query with several subselects. The query plan difference is at a certain place 12.10 (1) Index Name: ebase.acc_accnum Index Keys: accountnumber (Key-First) (Serial, fragments: 1, 2, 3) Fragments Scanned: (1) dbs2, (2) dbs3, (3) dbs4 Lower Index Filter: ebase.accounts.accountnumber >= '1280105921835900' Upper Index Filter: ebase.accounts.accountnumber = '1280105921835900' ) AND (ebase.accounts.accountnumber | |
Problem Summary: | |
**************************************************************** * USERS AFFECTED: * * Users of IDS prior to 12.10.xC13. * **************************************************************** * PROBLEM DESCRIPTION: * * 12.10 Optimizer calculates the selectivity of a subquery * * differently than in 11.50. * **************************************************************** * RECOMMENDATION: * **************************************************************** | |
Local Fix: | |
Solution | |
Workaround | |
not known / see Local fix | |
Timestamps | |
Date - problem reported : Date - problem closed : Date - last modified : | 17.03.2019 26.09.2019 26.09.2019 |
Problem solved at the following versions (IBM BugInfos) | |
12.10.xC13 | |
Problem solved according to the fixlist(s) of the following version(s) |