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How do I add a new table to an existing replication task and start CDC for it while not impacting/breaking the existing tables on going replication?

Suppose Oracle to Oracle engine. I already have 4 tables in task and cdc is running and in sync. Now I want to add 5th table to it. I did full load for it using native tool(data pump expdp/impdp using flashback_scn) after that I want to start CDC for it. Now do I create a new task for it or add to existing? Can someone please help me understand how to handle such requests.

TIA

nbqadri
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monto
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  • This does not look like a programming question. Are you facing an issue with some code that you can share with us? – RBT May 30 '22 at 06:34

1 Answers1

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You can add tables to an existing task. To add:

  1. Stop the task.
  2. Modify and add table and source filter (if any).
  3. Start the task and choose "Resume". This is critical, if you accidentally choose "restart" instead of "resume", the task will start from the beginning.

What to expect after adding the table: If the task is "Full load and ongoing changes" then the new table will go into FULL Load mode and once done, will move on to CDC.

If the task is "Ongoing changes only" then the new table will start getting CDC data from that point onwards. There will be no full load.

In either case, as long as the task is resumed, the rest of the tables will continue from the last CDC checkpoint and they will not be impacted. I hope it helps. thanks, Naveed.

nbqadri
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  • Thanks Naveed. If only CDC for existing task, isn’t data lost that got changed during the full initial load using expdp/impdp as we’re not specifying either SCN or timestamp? – monto Jun 02 '22 at 00:21
  • No data will not be lost for any table. Please have a look at the document by AWS : https://docs.aws.amazon.com/dms/latest/userguide/CHAP_Introduction.HighLevelView.html It gives you two key info: 1. During full load for a table, changes to that table will be cached on the replication server. 2. Every table has its own checkpoint. – nbqadri Jun 03 '22 at 07:06