Re: performance on delete the rows from a huge table

I think Daniel may have misspoken.

If seems to me that no matter how the delete is handled, by rowid or key columns, the need for incremental commits is dependend on the configuration of the rollback segments/undo tablespace. Either the rollback configuration can handle the delete as one transaction or it cannot and incremental commits will be necessary. When you delete a row the entire row and copies of associated index entries have to be written to the rollback segment area. The method of locating the row to be deleted by rowid or column values makes no difference.

The transaction would benefit from an index on x1, x2, x3, and x4. If these columns should comprise a unique key then the PK constraint exceptions clause can be used to locate the duplicate rows as Daniel points out.

HTH -- Mark D Powell -- Received on Sun Mar 20 2005 - 14:43:48 CST