Replication of large objects from blobspaces or sbspaces
retrieves the large object data directly from the blobspace or sbspace and then sends the data to the target database server.
It is possible that a transaction subsequent to the transaction that is being replicated can modify or delete a simple or smart large object that is trying to retrieve. If encounters a row whose large object (simple or smart) was modified or deleted by a subsequent transaction, does not send the data in the large object. In most cases, the subsequent transaction that modified or deleted the large object is also replicated, so the data again becomes consistent when that transaction is replicated. The data in the large object is inconsistent for only a short time.
The following conditions apply to replicating large objects that
are stored in blobspaces or sbspaces:
- does not support replication of large object updates performed outside of a row update.
- After you update a large object that is referenced explicitly
in the table schema, you must update the referencing row before can replicate
the updated smart large object. For example:
UPDATE table_name SET large_object_column = x - replicates updates to in-place smart large objects by sending a new copy of the entire smart large object. does not send only the logged changes to update smart large objects.
- does not support sharing out-of-row data (multiple references to a large object) during replication. If you try to replicate multiple references to the same large object on the source database server, does not re-create those references on the target database server. Instead, creates multiple large objects on the target database server.