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Is there any conceptual difference between a SERIALIZABLE Transaction and a Flashback Query?

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up vote 5 down vote accepted

They are completely unrelated concepts.

  • Serializable is a type of isolation level (read here for more info)
  • Flashback Query is an Oracle technology for getting querying data as it was at a certain point in time - for example, if certain conditions are met you can use Flashback Query to get those million rows back after committing that transaction that accidentally deleted them.
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"querying data as it was at a certain point in time" ... and with an isolation level of serializable I'm seeing the data as it was at the beginning of my transaction, regardless of any commits in other session, right? That's why I thought they are conceptually related ... –  Martin May 15 '11 at 15:06
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I see your point - they are similar in that sense, but used for very different purposes, serializable to "give each serializable transaction a "frozen" picture of the database at the point in time the transaction began" and flashback typically to save your blushes when something has gone awry –  Jack Douglas May 16 '11 at 20:29
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