Troubleshooting Db2

Attention: This topic contains Diagnosis, Modification, or Tuning Information.

This section discusses problem determination for the CICS® interface to Db2®.

How to identify Db2 threads that relate to CICS transactions

A thread executing in Db2 on behalf of a CICS transaction is identified by its correlation ID, which is set by the CICS Db2 Attachment Facility.

Db2 allows up to 12 bytes to be used for the correlation ID. The format of the 12-byte correlation ID is eeeettttnnnn where:
  • eeee is either COMD, POOL or ENTR indicating whether it is a command, pool or DB2ENTRY thread.
  • tttt is the transaction ID.
  • nnnn is a unique number.
Note: A correlation ID passed to Db2 can be changed only by the CICS Attachment Facility issuing a sign-on to Db2. If sign-on reuse occurs by a thread using a primary authorization ID which remains constant across multiple transactions, for example, by using AUTHID(name), only one sign-on occurs. In this instance, the tttt in the correlation ID does not match the running transaction ID. It is the ID of the transaction for which the initial sign-on occurred.