IT30917: SLOW-ALTERING A TABLE WHOSE INTERNAL SERIAL COUNTER WENT NEGATIVE WILL RESET THE SERIAL COUNTER TO 1

APAR status

• Closed as program error.

Error description

• A SERIAL column, once having reached its maximum value (2^31-1),
  will restart from 1, with internal serial counter now being
  negative - all working nicely as long as newly produced serial
  values can be entered into the table, i.e. wouldn't conflict
  with existing values in a unique index or constraint.
  An ALTER TABLE should also leave all of this, including current
  (next) serial value, unaffected, so inserting can proceed.
  
  Should such ALTER TABLE be conducted as a 'slow alter', though,
  the internal serial counter suddenly would be reset to 1,
  potentially leading to unexpected insert conflicts.
  

Local fix

• after such ALTER TABLE, or as soon as realizing you've got
  negative internal serial counter, run another ALTER TABLE MODIFY
  (<serial_column> SERIAL (<next_desired_positive_serial_value>));
  

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 (when      *
  * available).                                                  *
  ****************************************************************
  

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