IT30877: UPDATE STATS LOW USING SAMPLING CAN CAUSE -NAN VALUES IN SYSFRAGMENTS AND SYSINDEXES IN INDEX WITH FOT

APAR status

• Closed as program error.

Error description

• Consider a large table with 600 Mio rows and on this table there
  is a FOT index
  created on a serial column with unique values. When an update
  statistics low
  on this table/index is made and USTLOW_SAMPLE is set to 1, every
  second run
  on this update statistics returns -1223 on selects on
  sysfragments and sysindexes
  
  The problem column on sysfragments is the leaves colum.
  
  Additionally, queries on this table having a filter which can
  use the FOT index as
  the access path, it may return an -768 during the optimization
  of the query.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * Users of Informix Server prior to 12.10.xC14 and 14.10.xC4.  *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * See Error Description                                        *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Update to Informix Server 12.10.xC14 or 14.10.xC4.           *
  ****************************************************************
  

Problem conclusion

• Fixed in Informix Server 12.10.xC14 and 14.10.xC4.
  

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