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Sometimes Dbvisit support will may ask for a row history, also known as LogMiner dump to further analyse support issues. This means running LogMiner on the archive/online redo logs to obtain all changes on a particular row.

Setting up LogMiner

First, guess the date (or directly SCN) range A date range or Oracle SCN is needed for the period that is of interest. This is often constrained by archive logs available (only archive logs still known to the database are used by default).

A SYSDBA connection is needed. Please execute the following query:

begin

  DBMS_LOGMNR.START_LOGMNR(

   STARTTIME => sysdate-1,

   ENDTIME => sysdate,

   OPTIONS => DBMS_LOGMNR.DICT_FROM_ONLINE_CATALOG + DBMS_LOGMNR.CONTINUOUS_MINE

   );

end;

Querying the LogMiner data

After executing START_LOGMNR, the LogMiner data is available via the following command:

SELECT *

   FROM V$LOGMNR_CONTENTS

Note however, that running this query in full and without any where clause can take a very long time. Also, it's not advisable to insert the full data back into the database, as it would cause lot of archive logs generated and next query to the view would query these new logs, too.

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