IT17068: ASSERT FAILURE IN HASH_PROCESS_ALL_GROUPS POSSIBLE FOR QUERY WITH AGGREGATE FUNCTION AND GROUP BY CLAUSE

APAR status

• Closed as program error.

Error description

• A query with an aggregate function and group by clause may
  encounter an assert failure with a stack like:
  
  afstack
  mt_ex_throw_sig
  afsig_handler
  <signal frame>
  hash_process_all_groups
  group_open
  sort_open
  prepselect
  open_cursor
  sql_open
  sq_open
  sqmain
  spawn_thread
  th_init_initgls
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * Users of 12.10.xC7W1 and 12.10.xC7W2                         *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * An assertion failure may occur for a query under the         *
  * following conditions:                                        *
  *  - query has a group by clause                               *
  *  - at least one of the group by columns is of type varchar   *
  * or lvarchar, or an expression that results in a character    *
  * type                                                         *
  *  - there are many groups produced and the hash table used    *
  * for processing grouping operation overflowed to disk         *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Update to IBM Informix Server 12.10.xC8                      *
  ****************************************************************
  

Problem conclusion

• Problem Fixed In IBM Informix Server 12.10.xC8
  

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

  INFORMIX SERVER

• Fixed component ID

  5725A3900

Applicable component levels

• RC10 PSN

     UP