Changing Database Metadata

This procedure is required to prevent Replicat errors when changing the following metadata of the source database:

  • Database character set

  • National character set

  • Locale

  • Timezone

  • Object name case-sensitivity

If these changes are made without performing this procedure, the following error occurs:

2013-05-26 20:10:09  ERROR   OGG-05500  Detected database metadata mismatch between current trail file ./dirdat/_p/v1000000003 and the previous sequence. *DBTIMEZONE: [GMT]/[UTC]. 

This procedure stops Extract, and then creates a new trail file. The new database metadata is included in this new file with the transactions that started after the change.

  1. Stop transaction activity on the source database. Do not make the metadata change to the database yet.
  2. On the source system, issue the SEND EXTRACT command with the LOGEND option until it shows there is no more redo data to capture.
    SEND EXTRACT group LOGEND
  3. Stop Extract.
    STOP EXTRACT group
  4. On each target system, issue the SEND REPLICAT command with the STATUS option until it shows a status of "At EOF" to indicate that it finished processing all of the data in the trail. This must be done on all target systems until all Replicat processes return "At EOF."
    SEND REPLICAT group STATUS
  5. Stop the data pumps and Replicat.
    STOP EXTRACT group
    STOP REPLICAT group
    
  6. Change the database metadata.
  7. On the source system, issue the ALTER EXTRACT command with the ETROLLOVER option for the primary Extract to roll over the local trail to the start of a new file.
    ALTER EXTRACT group, ETROLLOVER
  8. Start Extract.
    START EXTRACT group
  9. Reposition the Replicat processes to start at the new trail sequence number.
    ALTER REPLICAT group, EXTSEQNO seqno, EXTRBA RBA
    
  10. Start the data pumps.
    START EXTRACT group
    
  11. Start the Replicat processes.
    START REPLICAT group