Re: Oracle instructor said...

>>I attended an Oracle training last week. The instructor told us to set
the initial extent and next extent for rollback segs 10% larger than the largest table in the database. Also set the min/max extents to 2 ONLY. This way no expanding/shrinking will take place. <<

Your instructor must not have any real world experience! I was tempted to use harsher language, but you may have misunderstood or he may have been talking about a specific case. In theory, what he said would be nice, but only in theory. Even then it just is not a practical solution.

Try to make each rollback segment extent large enough to hold the average transaction or better yet double the average transaction and then adjust the number of segments and number of extents to handle the number of concurrent update sessions that will be accessing your data. Make use of the 'alter session set transaction use rollback segment' command for that really big monster (hopefully) batch job, and call it a day.

Monitor warps and shrinks every now and then from v$rollstat and adjust as needed.

Good luck.

Mark Powell -- The only advise that counts is the advise that you follow so follow your own advise Received on Tue Feb 18 1997 - 00:00:00 CST