Root causes can include:
1. Bad record sent by Source.
2. DDL not posted or object not updated.
3. In general, the ORA-01036 error is encountered when there is a difference between the Source table structure and that of the Target table.
Similarly, a difference between Table structure and object cache files can result in the same error.
This can happen if a DDL to add a column is first performed on Target, then on Source, resulting in failed posting of DDL, as the column already
exists - ORA-01430: column being added already exists in table.
This results in the Target object cache missing the column and the ORA-01036 error is encountered.
