On Fri, Nov 19, 2010 at 1:09 PM, Tom Lane wrote:
> Jon Nelson writes:
>> On Fri, Nov 19, 2010 at 12:14 PM, Tom Lane wrote:
>>> Hard to comment about this with such an incomplete view of the situation
>>> --- in particular, data types would be a critical factor, and I also
>>> wonder if you're ad
Jon Nelson writes:
> On Fri, Nov 19, 2010 at 12:14 PM, Tom Lane wrote:
>> Hard to comment about this with such an incomplete view of the situation
>> --- in particular, data types would be a critical factor, and I also
>> wonder if you're admitting to all the columns involved.
> Here is an examp
On Fri, Nov 19, 2010 at 12:14 PM, Tom Lane wrote:
> Jon Nelson writes:
>> What influences the calculation of the 'width' value in query plans?
>
> It's generally the sum of the estimated column widths for all the
> columns needed at that particular level of the plan.
>
>> Specifically, I have two
Jon Nelson writes:
> What influences the calculation of the 'width' value in query plans?
It's generally the sum of the estimated column widths for all the
columns needed at that particular level of the plan.
> Specifically, I have two queries which both query the same set of
> tables via either
What influences the calculation of the 'width' value in query plans?
Specifically, I have two queries which both query the same set of
tables via either UNION or UNION ALL based on the presence (or
absence) of an aggregate function.
Like this:
SELECT a, b FROM foo_1 WHERE a = 'bar'
UNION
SELECT a
