SQL advice please

Morning all and Obnoxio, I am trying to delete some rows from a table where the same columns exist in another table, but there are two columns to check. I want to delete all rows in table_a where col_a and col_b are in table_b. The only way I have so far is as follows DELETE FROM table_a WHERE trim(col_a)||trim(col_b) IN (SELECT trim(col_a)||trim(col_b) from table_b) Does anyone know of a better way? Thanks Steve ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com

I don't know of the characteristics of your data, but since you have trim() in the query, I'm guessing that col_a and col_b is character data. That being the case, trim(col_a) || trim(col_b) might cause you to delete some rows that you don't mean to. For instance in suppost that the two columns in table_a are "abc", "defg". Now suppose that in table_b you have a row with "abcd", "efg". OPPS...... If the columns are the same size in table_a and table_b, perhaps it would be better not to trim. Steve Barnes wrote: > Morning all and Obnoxio, > > I am trying to delete some rows from a table where the same columns exist in > another table, but there are two columns to check. I want to delete all rows > in table_a where col_a and col_b are in table_b. > > The only way I have so far is as follows > > DELETE FROM table_a WHERE trim(col_a)||trim(col_b) IN > (SELECT trim(col_a)||trim(col_b) from table_b)> > Does anyone know of a better way? > > Thanks > > Steve > > ______________________________________________________ > Get Your Private, Free Email at http://www.hotmail.com