Object
Instantiation and Streams
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Set the instantiation SCN for the database
object at the destination database. The instantiation SCN
provides a directive to the Apply process running at the
destination database. It implies that only the database changes
committed after this SCN at the source database need to be
applied at the destination database. Instantiation is required
whenever an Apply process dequeues captured LCRs, even if the
Apply process sends the LCRs to an apply handler that does not
execute them.
Steps one through three are automatically
achieved when rules are added with the dbms_streams
package. The export/import method also sets up the instantiation
automatically.
In order to replicate changes to a database
object, the object must be prepared for instantiation at the
source database and the instantiation SCN is set for the object
at the destination database. By preparing an object for
instantiation, the lowest SCN is being set for which changes to
the object may need to be applied at destination databases. This
SCN is called the ignore SCN. The setup of the instantiation has
to be done after the Capture process is configured.
dbms_capture_adm has three
procedures which achieve the instantiation of objects. They are:
