April 1999
Intermediate to advanced
552 pages
15h 39m
English
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Replication of DDL
Oracle allows you to replicate DDL as well as DML. In other words, if you want to alter a table or create a new object such as an index or synonym, you can do so at the master definition site and automatically propagate the changes to the other master sites. The procedure DBMS_REPCAT.EXECUTE_DDL provides this functionality.
The DBMS_REPCAT.EXECUTE_DDL procedure queues changes in the
replication catalog queue (repcatlog), and the scheduled job
DBMS_REPCAT.DO_DEFERRED_REPCAT_ADMIN pushes the changes to the other
masters. Entries in the repcatlog are visible in
the DBA_REPCATLOG data dictionary view; a STATUS field contains the
value ERROR when errors occur; the MESSAGE field contains the error
text.
Not only does the repcatlog queue DDL to other master sites, it also queues replication administrative tasks such as quiescing the environment or adding new master sites. Chapter 12, describes these other activities in detail.