Re: [SQL] Using intersect in subquery

Bruce Momjian <maillist(at)candle(dot)pha(dot)pa(dot)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