The following errors are seen in target event_log when a materialized view exists on target where the underlying table may or may not be a part of replication:
Error 2016-01-21 22:27:03.638086 20880 1365956928 s:2 Poster: 12070 - OCITransCommit failed with ORA-12008. (posting from SID1, queue queue_name, to SID2) [module osp]
Error 2016-01-21 22:27:03.644732 20880 1365956928 s:2 Poster: failed to commit transaction session 2 in CommitFunc(): ORA-12008: error in materialized view refresh path.ORA-00942: table or view does not exist. Will exit Post.. (posting from SID1, queue queue_name, to SID2) [module opo]
Info 2016-01-21 22:27:03.665129 16418 3646488288 Poster exited with code=1, pid = 20880 (posting from SID1, queue queue_name, to SID2)
The refresh activities on materialized view on target are interfering with Post.
