Note: Before running Connect CDC, ensure that the setup steps for Oracle described in the Installation Guide are completed.
Connect CDC retrieves the data capture information from Oracle redo logs, eliminating the performance overhead of triggers from the user’s application.
The Oracle Change Selector runs inside the kernel as a separate thread and is responsible for:
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Locating the appropriate Oracle logs to read
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Retrieving data capture information for each active request
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Copying the changed data to the metabase
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Removing logs that are no longer needed
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Updating shadow tables.
The Change Selector periodically runs a query to process rows from the redo and archive logs. The Oracle Change Selector differs from the DB2 Change Selector, which is described in DB2 change selector.
Note: Index-organized tables are not supported for the Oracle Change selector.