Обсуждение: Re: [GENERAL] Illegal use of aggregates or non-group column in target list

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Re: [GENERAL] Illegal use of aggregates or non-group column in target list

От
"G. Anthony Reina"
Дата:
Jason wrote:

> select target, avg(reaction_time) from data_table GROUP BY target;
>
> That should do it.
>
> -Jason.
>

Wow! That works great. Thanks Jason.

It's interesting that "select target, avg(reaction_time) from data_table
GROUP BY target;" works but not "select target, avg(reaction_time) from
data_table;".

Doesn't the parser automatically group by the first variable returned?

-Tony



Re: [GENERAL] Illegal use of aggregates or non-group column in target list

От
Peter Eisentraut
Дата:
G. Anthony Reina writes:

> It's interesting that "select target, avg(reaction_time) from data_table
> GROUP BY target;" works but not "select target, avg(reaction_time) from
> data_table;".
>
> Doesn't the parser automatically group by the first variable returned?

The parser really doesn't know much about all of this. While you might
have a point that

    select field1, aggregate(field2) from table

doesn't have any other useful interpretation than an implied group by
field1, it's probably too much work to support such a non-SQL construct.

--
Peter Eisentraut                  Sernanders väg 10:115
peter_e@gmx.net                   75262 Uppsala
http://yi.org/peter-e/            Sweden