Stephen Frost wrote:
* Mark Woodward ([EMAIL PROTECTED]) wrote:
If I am asking for a specific column value, should I, technically
speaking, need to group by that column?
Technically speaking, if you're asking for a specific tuple, should you
be allowed to request an aggregation?
Only with the assumption that the value in the where clause is for a
unique column.
If you want min(col2) and avg(col2) where col1=x you can get it without
a group by, the same as if you put col1<x - if you want an aggregate of
all records returned not the aggregate based on each value of col1.
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.
--
Shane Ambler
[EMAIL PROTECTED]
Get Sheeky @ http://Sheeky.Biz
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