RE: Temporary Tablespaces

I believe that on startup the temporary file headers are rewritten. The temporary file is not formatted like a regular datafile would be for its declared size when added to a tablespace but instead is initialized when the space is used.

This should be in the manuals if I can grab a couple of minutes to go hunting.

HTH -- Mark D Powell --

-----Original Message-----

From: Hollis, Les [mailto:Les.Hollis_at_ps.net] Sent: Monday, January 10, 2005 11:51 AM
To: Powell, Mark D; Oracle-L
Subject: RE: Temporary Tablespaces

Well good question. Got me to thinking. I know for sure that if you created a tablespace type temporary using a standard datafile, you have this issue. But, I am not sure with a tempfile. Need to do a little research.

First question comes to mind....does it actually create the tempfile? When you shutdown the database, the tempfile is still in your operating system. Instance/database startup, it reuses the same file since that is defined in the data dictionary. So I don't see how it actually recreates it. It reuses that file and data dict information. If the file is still there and the data dict info is still there, then I am willing to bet (maybe a buck or two 8~)) ) that the segment info is retained in the data dictionary.

Anyone else with input?

-----Original Message-----

From: oracle-l-bounce_at_freelists.org
[mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Powell, Mark D Sent: Monday, January 10, 2005 9:25 AM
To: Oracle-L
Subject: RE: Temporary Tablespaces

Les, If the temp tablespace is created using tempfiles which are in turn "re-created" every time the instance is started how is it that pmon has to
clean up a log of small extents each time the instance starts? What extents?

• Mark D Powell --

-----Original Message-----

From: oracle-l-bounce_at_freelists.org
[mailto:oracle-l-bounce_at_freelists.org]On Behalf Of Hollis, Les Sent: Sunday, January 09, 2005 2:27 PM
To: Bryan Wells; Oracle-L
Subject: RE: Temporary Tablespaces

1. create default temporary tablespace tspacename

CREATE TEMPORARY TABLESPACE temp
TEMPFILE '/u01/oradata/temp01.dbf' SIZE 500M EXTENT MANAGEMENT LOCAL UNIFORM SIZE 4M; =20 (Set your uniform size to a reasonable size based on your database size. DO NOT use small extents. Use 5m, 10m, even up to 100m if your tspace is large enough If you set it too small, you run in to the iissue of PMON running a long time to clean up the huge number of small extents each time the instance starts.)

After tablespace is created,=20

ALTER DATABASE=20
DEFAULT TEMPORARY TABLESPACE temp;

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http://www.freelists.org/webpage/oracle-l Received on Mon Jan 10 2005 - 11:01:37 CST