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Monday, 31 October 2011

Useful way to improve peformance of bulk DELETE

delete from table1
where
rowid in ( select rowid
           from table1 group by rowid, col_id
           minus
           select max(rowid)
           from table1 group by col_id);
 

2 comments:

  1. Could you please explain?

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  2. This comment has been removed by the author.

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