Configuration parameter and table setting requirements v7
Depending on the multi-master replication system environment, you might need certain configuration settings for the conflict resolution process to operate properly.
The following are required only for the log-based method. These do not apply to the trigger-based method.
track_commit_timestamp. Any Postgres 10 and later database server containing a primary node must have its
track_commit_timestampconfiguration parameter enabled. The
track_commit_timestampparameter is located in the
track_commit_timestampisn't enabled, then update/update conflicts aren't automatically resolved such as by using the earliest timestamp of the conflicting transactions. As a result, these conflicting transactions are left in a pending state. See Automatic conflict resolution example for an example of how update/update conflicts are automatically resolved.
REPLICA IDENTITY FULL. If
update/update conflictsare expected to occur on a given publication table, then you must set the
REPLICA IDENTITYsetting for the table to
FULLon every primary node. The case where update transactions occur on separate primary nodes but updating different columns in the same row isn't considered an update/update conflict. However, if
REPLICA IDENTITYisn't set to
FULL, then this case is recorded as an update/update conflict.
REPLICA IDENTITY option to
FULL using the
ALTER TABLE command as shown by the following:
The following is an example of the
ALTER TABLE command:
You can display the
REPLICA IDENTITY setting with the
PSQL utility using the
In addition to conflict resolution requirements, you might need the
REPLICA IDENTITY FULL setting on publication tables for other reasons in Replication Server. See Table settings and restrictions for table filters for additional requirements.