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There's a few posts about direct path and dataguard but I just want to understand exactly how it actually works.

How maybe I made an incorrect assumption, but if direct path means it writes to the data files (as per the docs) then doesnt that mean no redo is generated?

And if no redo is generated then how does dataguard work? ( which is soley based upon transferring redo to the standby machine right? )

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If the database is setup correct: no direct path load. If a standby database is depending on the changes captured on the primary database, the primary database should be setup with force logging.

If for some reason the force logging setting is not in place, after such an operation the affected datafiles should be transferred to the standby site[s]. Failing to do so will make queries on the loaded parts of the table[s] in the standby database to fail.

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  • As I thought then. Adding dataguard to an existing system which already makes use of direct path loads is therefore something to be considered very carefully. – Codek Apr 25 '14 at 15:09
  • yes, accept that the performance advandage of direct path load get's lost when changing the database to force logging mode or add the complexity for the df copies and recoveries at the standby site. – ik_zelf Apr 25 '14 at 15:23

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