If you use CICS or IMS applications to update both the Teradata Database and any other recoverable resource or database within the same logical unit of work, consider using the Two-phase commit protocol. Two-phase commit is available only for the following releases of the Teradata Database:
- Teradata Database for UNIX, version 2 release 2 (or later)
- Teradata DBS for TOS, version 1 release 5 (or later).
If you attempt to use the Two-phase commit DBCAREA option mode in an unsupported environment, CLIv2 rejects the attempt with the return code of “CLI0200 TWO PHASE COMMIT OPTION REQUIRES A COORDINATOR.” Specifying the Transaction-semantics DBCAREA option of 'A' prevents use of Two-phase commit.
When you do not use the Two-phase commit protocol, an application is subject to failure windows that can leave the databases in an inconsistent or indeterminate state. The Two-phase commit protocol eliminates those failure windows.
For information on how the Teradata Database participates in the Two-phase commit protocol, see the Database Administration (B035-1093) manual or the Database Design (B035-1094) manual.