Performance problem with deleteing large number of rows from a table

I am having performance problem with my application while deleting large number of rows from a table.

How can I imporve performance of deleting large number of rows > 500000 from a table with the following constraints.

1. Table does not have indexes, PK etc (This should help deletion -- Hope I am right)
2. Multiple clients can issue delete quries for deleting subset of table data. (For example table might contain 50,0000 rows for product
3. If a user loading fresh data for product A he will first delete the previous data of product A and then upload the new data, similarly another user might be working with product B etc and they might be running the delete query simulataneouly)
4. User might not have DDL rights so creating a new table and deleting the old one is not possible.

Currently we are using delete quries which is taking a lot of time.

Faisal Received on Thu Aug 10 2006 - 02:21:42 CDT