relation betweel rollback segment and redo logs

[palwinder]

what is the relation between rollback segment and redo logs?

 

[JamesGordon]

A rollback segment hold the data that was changed and is used by the server to ensure that others looking at the same data have a consistant view of the data until you commit it.
The redo is a log of events that happen on the system and is written to before the dbwr (database writer) writes the changes to the datafiles. It also ensures that if the database crashes, on startup, it can roll forward any changes that were written to the redo log but not already written to the datafiles.
Probably does a lot more, but that is the jist of things.

 

[rtefft]

In simple terms:

Rollback segments hold the UNCOMMITTED changes to the database, and Redo Logs hold the COMMITTED changes to the datase until the changes are actually made by the DBWR process. As soon as you issue a commit, your changes move from the RB segments to the Redo logs.

Rich ____________________________
Rich Tefft
PL/SQL Programmer

 

[gansen]

Rollback segment hold uncommited data, for further rollback
Redo logs has commited and uncommited transaction.,

Once you issue a commit, rollback segment for that transaction is removed and ready to hold data for next transaction