LI71080: INCORRECT QUERY RESULT BECAUSE THE OUTPUT CARDINALITY HAS SET TO 1.

DB2 UDB Version 8.1 FixPak 16 (also known as Version 8.2 FixPak 9 )

APAR status

• Closed as program error.

Error description

• A query returns only one row per symmetric
  multiprocessing (SMP) agent, even though more rows are expected.
  In general, the scenario in which this problem can occur has the
  following characteristics:
  * SMP parallelism is on (the database manager configuration
  parameter max_querydegree is set to a value that is greater than
  1)
  * A materialized query table (MQT) is present; MQT matching is
  attempted during query compilation, and a candidate MQT is
  expanded only if:
    * The MQT is not in check pending state
    * The MQT is either refresh immediate or refresh deferred and
    the refresh age has been set to 'ANY'
    * The MQT is dependent on at least one base table or nickname
    of the query
  * The query has a chain of equivalent join predicates on the
  primary key or unique key columns for three or more base tables;
  for example:
  t1.pk = t2.pk and t2.pk = t3.pk
  
  USERS AFFECTED: DB2 UDB Version 8.1 FixPak 9, 10 and 11 (not
  earlier than FP9)
  

Local fix

Problem summary

• A query returns only one row per symmetric
  multiprocessing (SMP) agent, even though more rows are expected.
  In general, the scenario in which this problem can occur has the
  following characteristics:
  * SMP parallelism is on (the database manager configuration
  parameter max_querydegree is set to a value that is greater than
  1)
  * A materialized query table (MQT) is present; MQT matching is
  attempted during query compilation, and a candidate MQT is
  expanded only if:
    * The MQT is not in check pending state
    * The MQT is either refresh immediate or refresh deferred and
    the refresh age has been set to 'ANY'
    * The MQT is dependent on at least one base table or nickname
    of the query
  * The query has a chain of equivalent join predicates on the
  primary key or unique key columns for three or more base tables;
  for example:
  t1.pk = t2.pk and t2.pk = t3.pk
  
  USERS AFFECTED: DB2 UDB Version 8.1 FixPak 9, 10 and 11 (not
  earlier than FP9)
  

Problem conclusion

• Problem fixed in FP12
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  DB2 UDB EXE LIN

• Fixed component ID

  5724E4904

Applicable component levels