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  1. Debezium
  2. DBZ-3786

Tutorial shows incorrectly shows "op": "c" for initial change events


    • Icon: Bug Bug
    • Resolution: Done
    • Icon: Minor Minor
    • 1.8.0.Beta1
    • 1.6.0.Final
    • documentation
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      When running through the tutorial at https://debezium.io/documentation/reference/1.6/tutorial.html, I got confused at the https://debezium.io/documentation/reference/1.6/tutorial.html#viewing-change-events step where it showed "op": "c" in its sample output, but running through the steps myself I saw "op": "r". The other text in the tutorial described "r" as being only applicable to a "non-initial snapshot", but as far as I could tell, this was an initial snapshot, so I was concerned I'd made a mistake in running through the tutorial steps. However, I eventually found my way to https://debezium.io/documentation/reference/1.6/connectors/mysql.html#mysql-snapshot-events that explained:

      The MySql connector emits snapshot events using the "r" operation type (READ). In case you want the connector to emit snapshot events as "c" events (CREATE, as done incorrectly in earlier versions), this can be achieved using a Simple Message Transforms (SMT).

      So that seems to indicate I was seeing a newer, corrected behavior, but the sample output in the tutorial has not been updated to reflect that.

      FWIW, when I reported this on Gitter, jpechane suggested I might submit a docs PR with the fix. I think I see where in the repo this change would be made, but I feel I should also mention that there were other parts of the tutorial that also seemed out of sync, e.g. the many steps shown in the https://debezium.io/documentation/reference/1.6/tutorial.html#watching-connector-start-up did not match what I observed, plus I noticed way less SQL output than is shown there. Overall it seems like it could probably benefit from another pass from someone who knows & can explain its current behaviors/outputs better than I could as a newbie.

            ccranfor@redhat.com Chris Cranford
            philrz Phillip Rzewski (Inactive)
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