Sunday, November 2, 2008

Oracle : TEMPORARY Tablespaces and TEMPFILES

Allocation of Temporary Segments for Temporary Tables and Indexes


Oracle allocates segments for a temporary table when the first INSERT into that table is issued. (This can be an internal insert operation issued by CREATE TABLE AS SELECT.) The first INSERT into a temporary table allocates the segments for the table and its indexes, creates the root page for the indexes, and allocates any LOB segments.

Segments for a temporary table are allocated in a temporary tablespace of the user who created the temporary table.

Oracle drops segments for a transaction-specific temporary table at the end of the transaction and drops segments for a session-specific temporary table at the end of the session. If other transactions or sessions share the use of that temporary table, the segments containing their data remain in the table.

http://download.oracle.com/docs/cd/B19306_01/server.102/b14220/logical.htm#sthref383

http://download.oracle.com/docs/cd/B19306_01/server.102/b14220/logical.htm#i5696

http://beginapps.blogspot.com/2008/04/how-to-use-temporary-tablespaces.html

http://www.orafaq.com/node/2

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