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oracle total recall 11g – how are sys_fba tables created – for the new oracle dba





you are a new oracle dba and you would like to know how the sys_fba tables are created as part of the oracle 11g total recall functionality.

What Event Triggers The Creation Of The Sys_fba* Tables For Total Recall? [ID 1302393.1]

  Modified 27-JUN-2011     Type HOWTO     Status PUBLISHED  

In this Document
Goal
Solution
References


Applies to:

Oracle Server – Enterprise Edition – Version: 11.2.0.1 and later   [Release: 11.2 and later ]
Information in this document applies to any platform.

Goal

Need an understanding of what triggers the creation of the sys_fba*  tables for Total Recall or Flashback Data Archive.  There is a delay in the creation of the sys_fba* tables after a table is enabled for Total Recall or Flashback Data Archive.

Solution

This response came from Oracle development in BUG 10363918 (closed as not a bug):.

Regarding there being a delay in the SYS_FBA* tables, this is how it has been designed, this is not a bug.

The SYS_FBA_* tables are created lazily and queries on SYS_FBA_* tables are not supported.  The history tables are created lazily when there is history to be generated. There should be no need to query the history tables directly because flashback “as of” and “versions” queries are transparently used to access the history tables as needed.  If there is no history generated (DML/DDL issued on the table after enabling flashback archive), the history tables are not created. Tracking the creation of the history tables is only meaningful after changes have been made to the base table.  By default FBAR (Flashback Archive) wakes up at 5 minutes interval  in 11.2.0.1 and performs it’s activities like creating history tables (SYS_FBA_*) etc. In 11.2.0.2.0 > it wakes up every 6 seconds.

Regarding the creation of history tables:

For Non-RAC env:
After enabling flashback archive for a table, FBAR would create history tables when it wakes up next for scanning. In this case, the delay could be max up to 5 minutes.

For RAC env:
After enabling flashback archive for a table, FBAR doesn’t create history tables until a DML is performed.
Post DML operation, at first FBAR scan these tables would be created.

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