Mark Woodward wrote:
>> Stephen Frost wrote:
>>
>>
>>> select ycis_id, min(tindex), avg(tindex) from y where ycis_id = 15;
>>>
>> But back to the query the issue comes in that the ycis_id value is
>> included with the return values requested (a single row value with
>> aggregate values that isn't grouped) - if ycis_id is not unique you will
>> get x number of returned tuples with ycis_id=15 and the same min() and
>> avg() values for each row.
>> Removing the ycis_id after the select will return the aggregate values
>> you want without the group by.
>>
>
> I still assert that there will always only be one row to this query. This
> is an aggregate query, so all the rows with ycis_id = 15, will be
> aggregated. Since ycis_id is the identifying part of the query, it should
> not need to be grouped.
>
> My question, is it a syntactic technicality that PostgreSQL asks for a
> "group by," or a bug in the parser?
>
>
AFAIK what you want is not per sql spec. What if you had instead written
select ycis_id, min(tindex), avg(tindex) from y where frobnitz(ycis_id) = 15;
? I think you are expecting too much reasoning from the engine.
cheers
andrew
