Db2 thread identification

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 12 byte correlation ID is made up as eeeettttnnnn where eeee is either COMD, POOL or ENTR indicating whether it is a command, pool or DB2ENTRY thread; tttt is the transid, and 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 will occur. 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.