| Latest versions | fixlist |
| 14.10.xC10 |
 |
| 12.10.xC16.X5 |
|
| 11.70.xC9.XB |
|
| 11.50.xC9.X2 |
|
| 11.10.xC3.W5 |
|
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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) | |
