Oracle CDC V2 Connector

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CDC runtime properties in mapping tasks

When you create or edit a mapping task that processes change data from a CDC source, you can set optional properties on the

CDC Runtime

page. These properties are used when the mapping task runs.

The following table describes the optional CDC runtime properties:

Property	Description
Maximum Rows Per Commit	Maximum number of change records in a UOW that the mapping task can process. When this maximum is reached, the UOW change records are committed on the target. Valid values are 0 through 999999999. Default is 0, which causes this property to be ignored.
Minimum Rows Per Commit	Minimum number of change records that must exist in a UOW before the PWX CDC Reader can request a real-time flush of the change records to the target. Valid values are 0 through 999999999. Default is 0, which causes this property to be ignored.
Maximum Latency in Seconds	Maximum number of seconds that the PWX CDC Reader waits for more change records before flushing change data from partially filled or empty blocks and returning control to Data Integration. Valid values are 2 through 360. Default is 2.
Real-time Flush Latency in Milliseconds	Number of milliseconds that must elapse before the PWX CDC Reader requests a real-time flush of uncommitted data in the change data stream to the targets defined in the mapping. Valid values are -1 through 999999999. Default is 2000. To control commit processing, you can also use the UOW Count , Maximum Rows Per Commit , and Minimum Rows Per Commit properties.
Restart Point	Displays the restart point in read-only mode. The restart point indicates the position in the change data stream from which the PWX CDC Reader will start reading change records for a source table. Usually, you set the restart point before running the mapping task the first time to coincide with the time when the target table was materialized. You might also need to set the restart point to reprocess change records or to perform some testing. To set the restart point, click Select . If you do not specify a restart point, the mapping task starts or restarts from the end of log by default.
Restart Revision	Displays the restart-point revision number in read-only mode. When you navigate to the CDC Runtime page, open the Select Restart Point dialog box, and click OK , the revision number is incremented by 1, regardless of whether you changed the restart point. During a single mapping-task edit session, the revision number is incremented by 1 only once, even if you return to the Select Restart Point dialog box multiple times. When a new revision is created, the CDC Connector ignores the restart information in the PM_REC_STATE recovery table and uses the specified restart point the next time you run the mapping task. If you run the mapping task and then change to a different source object, you must either increment the restart revision number or create a new mapping task. Initial value is 0.
UOW Count	Number of units of work (UOWs) in the change data stream that the PWX CDC Reader processes before it requests a real-time flush of change records to the targets in the mapping. Valid values are -1 through 999999999. The values -1 and 0 cause this property to be ignored. Default is -1.
Update as Delete and Insert	Controls whether each SQL update that is captured from a source table is processed as an update or as a delete followed by an insert. You can select this property to handle changes to primary keys in source tables, in which case the insert record contains the key changes. Otherwise, leave this property cleared for normal processing of inserts, updates, and deletes. By default, this check box is not selected, which causes updates to be processed as update operations.
Continuous Extraction	Controls whether the mapping task runs continuously to capture change data from the source. Selecting this property indicates that the mapping task runs until it is stopped in the Monitor. By default, this check box is not selected and the mapping task stops after a single execution.