Re: [SQL] Using intersect in subquery

Bruce Momjian <maillist@candle.pha.pa.us> writes:
> Try 6.5.  We fixed some Intersect stuff.
>> 
>> select * from Table1
>> where KeyField1 in
>> (select KeyField2 from Table2 where  somecondition
>> intersect
>> select KeyField3 from Table3  where somecondition);
>> 
>> (I believe) I am running PG 6.4.  The INTERSECT by itself works, but not in
>> a subquery.
>> 

No, it still won't work --- the current grammar specifies SubSelect not
select_clause as the kind of select you can put inside an expression.
Not sure what it would take to fix this; I have a feeling that just
changing the grammar wouldn't be good enough :-(.  Better add it to the
TODO list:* Support UNION/INTERSECT/EXCEPT in sub-selects
        regards, tom lane