DB2 - Problem description
Problem IC87348 | Status: Closed |
IN A DPF ENVIRONMENT THE COLLECTION OF SECTION ACTUALS MIGHT SHOW "NA" AT SOME OPERATORS IN THE EXPLAIN OUTPUT | |
product: | |
DB2 FOR LUW / DB2FORLUW / 970 - DB2 | |
Problem description: | |
The problem can occur when all the following conditions are satisfied: 1. DPF environment with table distributed across > 1 database partitions 2. the query includes a predicate applied to the table access that indicates only a single database partition needs to be accessed, such as when the hash distribution key is bound to a constant value by means of an equality predicate or a predicate using the dbpartitionnum() function to filter rows only from a single database partition 3. the query qualifies 0 rows from the table For example, if table T is hash distributed across multiple data partitions on column X, then the following query satisfies conditions 1 and 2: SELECT * FROM T WHERE X = 1 If the table doesn't contain any rows matching "X=1", then condition 3 is satisfied and the section actuals information in the db2exfmt output will show "NA": Rows Actual RETURN ( 1) Cost I/O | 0 0 DTQ ( 2) 12.0482 NA | 0 NA <=== A value of NA is unexpected TBSCAN ( 3) 9.6526 NA | 0 NA TABLE: TEST T1 Q1 | |
Problem Summary: | |
**************************************************************** * USERS AFFECTED: * * DPF * **************************************************************** * PROBLEM DESCRIPTION: * * See Error Description * **************************************************************** * RECOMMENDATION: * * Upgrade to DB2 9.7 Fix Pack 8 * **************************************************************** | |
Local Fix: | |
available fix packs: | |
DB2 Version 9.7 Fix Pack 8 for Linux, UNIX, and Windows | |
Solution | |
DB2 9.7 Fix Pack 8 - Section actuals in a DPF environment for a predicate returning rows for one node will show operator values. | |
Workaround | |
not known / see Local fix | |
BUG-Tracking | |
forerunner : APAR is sysrouted TO one or more of the following: IC91294 follow-up : | |
Timestamps | |
Date - problem reported : Date - problem closed : Date - last modified : | 18.10.2012 08.04.2013 08.04.2013 |
Problem solved at the following versions (IBM BugInfos) | |
9.7.FP8 | |
Problem solved according to the fixlist(s) of the following version(s) | |
9.7.0.8 |