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http://ocp.community.ge/post/Logminer-Gives-Error-In-Memory-Undo-is-unsupported-What-is-In-memory-undo.aspx

Logminer Gives Error - In Memory Undo is unsupported!

Why logiminer Gives error?

We see that structure of redo entries is different, for IMU logminer can’t recover full picture of transaction in same time.

Now see on metalink, note ID 428167.1 which give us solution for avoid error “In Memory Undo is unsupported” in future!

1.Logminer cannot always populate all the fields of the v$logmnr_contents this is

because the redo may/may not have all the information that we need for every column. Adding Supplemental Logging will help in more info being logged in the redo being generated, helping populate more values. This can be done by the following commands: SQL> ALTER DATABASE ADD SUPPLEMENTAL LOG DATA (PRIMARY KEY, UNIQUE INDEX) COLUMNS; SQL> ALTER SYSTEM SWITCH LOGFILE; Additionally, it is not unusual for 10g to generate more redo than previously seen in earlier versions.

2: Logminer cannot always populate all the fields of the v$logmnr_contents this is because the redo may/may not have all the information that we need for every column, you need to enable supplemental logging on the database following Supplemental logging is required to receive reliable and consistent information from logminer. Without supplemental logging enabled, the redo may not contain enough information for LogMiner to construct the correct sql_redo (or any sql_redo in the case of in-memory undo, IMU). LogMiner does not work with IMU and turning supplemental logging on disables IMU. Please enable supplemental logging as per to eliminate these messages and update whether you still encounter the UNSUPPORTED messages.

3: Logminer may not be able to find sql_redo for transactions that were created before supplemental

logging is enabled. It will only work for redo's which contains information to extract the correct sql_redo

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