Problem: SE 5.06, outer joins and nulls

I'm trying to do an outer join between two tables, say: domtable(id, base_value) subtable(id, current_value) where a subtable record is created when the base_value in the domtable is no longer valid as a current value. my query runs like so: select domtable.id, domtable.base_value from domtable, outer subtable where subtable.current_value is null and domtable.id = subtable.id One problem is that the above query returns all rows driven by domtable regardless if the row's counterpart in subtable has a null value in current_value or not. Additionally, when I change the query slightly: select domtable.id, subtable.current_value from domtable, outer subtable where subtable.current_value is not null and domtable.id = subtable.id both of these queries return the same set of domtable.id suggesting that subtable.current_value is both null and not null for rows in the result table where there was not a subtable record to correspond with the domtable record driving the outer join. From the Informix Guide to SQL, Tutorial, December 1991 on P 3-19 in the section on Outer Joins, I see: "In an outer join, the result contains the combination of rows from the tables that satisfy the join conditions [domtable.id = subtable.id]. Rows from the dominant table that would otherwise be discarded are preserved, even though no matching row was found in the subservient table. The dominant table rows that do not have a matching subservient table row receive a row of nulls before the selected columns are projected." To make matters worse, these "not quite nulls" match every relational operation I apply to the field that is supposed to be null (real nulls fail these) Is this a known bug? I've seen some rumblings on here that indicate that this might be, but I couldn't tell if the problem that was briefly mentioned was the same as mine. -------------------==== Posted via Deja News ====----------------------- http://www.dejanews.com/ Search, Read, Post to Usenet