How to make faster deletion on duplicated records?

Hi, all,

I tried the following two ways to delete duplicate records on a 5000 records table:

1).  	DELETE FROM Customer C
	WHERE C.rowid > ( SELECT MIN(X.rowid)
			FROM Customer X
			WHERE X.phone = C.phone);

2).	CREATE TABLE temp
	AS


	(SELECT * FROM Customer C

	WHERE C.rowid > ( SELECT MIN(X.rowid)
			FROM Customer X
			WHERE X.phone = C.phone)
	);

	DROP TABLE Customer;

	CREATE TABLE Customer
	AS


	(SELECT * FROM temp);


	DROP TABLE temp;

The second way is a little faster than the first one, but both of them took about 40 minutes to finish the deletion. Even after I indexed on the "phone" column, the performance is not improved.

Is there any better way to do that? Thanks. Received on Thu Mar 06 1997 - 00:00:00 CST