Re: Redo/Transaction Log

Redo logs are a fixed size. Oracle alternates between a minimum of two redo logs. When one fills, it changes to the next one and archives the full one automatically and so on. You can force a log switch at any time with Alter system switch logfile; but this won't save you any space. If the archived logs are being stored on the same disk, that could be taking your extra space. Select * from V$parameter where name = 'archive_log_dest%'; to check for the location of the archived logs. Your tablespaces may be set to autoextend (Bad Idea for a production database) Once an object takes space it doesn't give it up without a fight. You might need to move data to another table then truncate the table and move it back to reclaim the space. Only truncating a table resets it's high water mark.

Hope this helps.

Dave

bjhhbj_at_yahoo.com (bjh) wrote in message news:<92e42823.0201181157.bee9036_at_posting.google.com>...
> I'm asking this question from a SQL Server perspective, so I apologize
> if I don't have the Oracle terminology correct.
>
> In SQL Server, you can truncate the transaction log periodically to
> preserve space when you run very large update statements.
>
> In Oracle, is there a way to truncate the Redo logs? I have run a
> series of update statements and delete statements against an Oracle
> database. I noticed that the space availabe has decreased even though
> the number of records in the database is drastically lower. I assume
> this is due to a large Transaction/Redo log created by the updates.
>
> I would like to recover this space before proceeding.
Received on Sun Jan 20 2002 - 00:50:52 CET