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RSSChange Data Capture

MISSING Streams multi-version data dictionary

I was testing out the effects of making changes to tables within the source database in a Change Data Capture (CDC) configuration on Oracle. I was adding columns, removing columns, etc and seeing what changes I needed to make in the destination database in order to keep everything working as it should. I then tried […]

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ORA-31538 Change Set Disabled

The Problem Using CDC on Oracle version 11.2.0.1 and running with Asynchronous Autolog mode for the capture at a separate downstream database. I was trying to activate a previously created subscription when I received the following: — When activating a subscription begin dbms_cdc_subscribe.activate_subscription( subscription_name => ‘Acturis_Subscrpt’); end; / ERROR at line 1: ORA-31538: change set […]

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Error 604 received logging on to the standby

When setting up the environment for Change Data Capture (CDC), which uses streams and, in our case, archive redo log shipping, I noticed that it wouldn’t work straight away and there were some errors in the alert log of the primary database: Wed Apr 07 09:37:59 Error 604 received logging on to the standby I […]

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ORA-31403: change table already contains a column

Imagine the scenario: You have a change set and your Change Data Capture (CDC) configuration has been running smoothly for a few weeks now. Your boss tells you that there is an upgrade planned soon and that the provisional changes included adding columns to the source tables that you have based your change tables on. […]

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ORA-31514: change set %s disabled due to capture error

Whenever you come across this error, the first place to look is in the view DBA_APPLY_ERROR. This view will show you the error message causing the problem. You may also find it in a trace file and/or the alert log for the DB. If you set up the change capture so that the STOP_ON_DDL parameter was set toTRUE, […]

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ORA-26663 – When Dropping a CDC Change Set

There are lots of times when you are new to a technology that you want to wipe the slate clean and start your process again because you are not sure where it went wrong. I attempted this after receiving several errors within Change Data Capture, and the capture and/or apply processes were receiving the ORA-26663 error. So, […]

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Spaces in Source Table show as NULL in Change Tables

The Problem We came across an issue within our Change Data Capture configuration where we would get NULL values in our change tables, but we didn’t understand why because we had unconditional log groups for the columns which were showing as NULL in the change table. The Cause Spaces input by users caused the NULL […]

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V$STREAMS_CAPTURE – Waiting for Dictionary Redo

If you are configuring streams, or in my case Change Data Capture (CDC), you will be familiar with the wait events show in the v$streams_capture Oracle view. Once of these wait events is the “Waiting for Dictionary Redo” event. This is what is shown while the streams capture process is waiting to receive the dictionary […]

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DBMS_CAPTURE_ADM.BUILD Hangs

Having recently set-up Change Data Capture (CDC) on a development environment which in use, I was running a command to build a copy of the data dictionary into the redo log, as below: set serveroutput on variable f_scn number; begin :f_scn := 0; dbms_capture_adm.build(:f_scn); dbms_output.put_line(‘The first_scn value is ‘ || :f_scn); end; / Looking at […]

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