Capture Process Creation
A Capture process that captures changes to
the local source database can be created, or a Capture process
that handles the database changes that occur at a remote site
can be created. The atter method is known as Down Streams
capture. If a Capture process runs on a Down Streams database,
redo log files from the source database are copied to the Down
Streams database, and the Capture process captures changes in
these redo log files at the downstream database. Configuration
of Down Streams capture is covered in later chapter.
Oracle provides many procedures that can be
used to create the capture process. Any of the following
procedures can be used to create a local Capture process:
-
dbms_streams_adm.add_table_rules
-
dbms_streams_adm.add_subset_rules
-
dbms_streams_adm.add_schema_rules
-
dbms_streams_adm.add_global_rules
-
dbms_capture_adm.create_capture
Each one of these methods will be examined
as will the circumstances in which each one is appropriate.
Figure 4.5 Methods of Creating
the Capture Process
As shown in Figure 4.5, there are three
procedures in the package dbms_streams_adm, each one of
these can create a Capture process with the specified name if it
does not already exist. They also create either a positive or
negative rule set for the Capture process if the Capture process
does not already have such a rule set. They can also add table,
schema, or global rules to the rule set.
