Type-2 CDC

Use Type-2 CDC #

From version 22.07.19.3 onwards, Arcion supports Type-2 CDC. Type-2 CDC enables a target to possess a history of all transactions performed in the source.

Supported platforms #

Arcion supports Type-2 CDC for the following targets:

Overview #

Type-2 CDC enables a target to possess a history of all transactions performed in the source. For example:

  • An INSERT in the source appears as an INSERT in the target.
  • An UPDATE in the source appears as an INSERT in the target with additional metadata like operation performed, time of operation, and so on.
  • A DELETE in the source appears as an INSERT in the target. For example, INSERT with OPER_TYPE as DELETE.

Arcion supports the following metadata related to source-specific fields:

  • USER_QUERY_TIMESTAMP: Time when the user on source fires a query.
  • EXTRACTION_TIMESTAMP: Time when Replicant detects the DML from logs.
  • OPERATION_TYPE: Type of the operation (INSERT, UPDATE, or DELETE).

You must enable full row logging in the source to use Type-2 CDC.

Limitations #

Support for Type-2 CDC possesses the following limitations:

  • Type-2 CDC works on sources that support CDC.
  • Type-2 CDC works in realtime and full modes.

Enable Type-2 CDC #

  1. Set cdc-metadata-type and replay-strategy to the following values under the realtime section of the Applier configuration file:

    realtime:
      cdc-metadata-type: TYPE2_CDC
      replay-strategy: NONE
    
  2. In the Extractor configuration file of source, set the following parameter under the snapshot section:

    snapshot:
      csv-publish-method: READ