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[GENERAL] [RFE] auto ORDER BY for SELECT

Chris Angelico rosuav at gmail.com
Tue Jan 24 03:30:16 EST 2012 
Whoooooops. Wrong list. *sigh* At least there's some variety - it's
not Savoynet this time.

Disregard the mad guy in the corner, he's not saying anything useful anyway...

ChrisA

On Tue, Jan 24, 2012 at 7:29 PM, Chris Angelico <rosuav at gmail.com> wrote:
> On Mon, Jan 23, 2012 at 11:17 PM, Douglas Eric <sekkuar at hotmail.com> wrote:
>> I suggest to change this behavior. If one makes a SELECT statement without
>> any ORDER BY, it would be
>> clever to automatically sort by the first primary key found in the query, if
>> any.
>> The present behavior would still be used in case of queries without any
>> primary key fields.
>
> This would require that work be done without text commanding it, which
> is IMHO a bad idea. Generally, SQL follows the principle that more
> text --> more work: compare SELECT and SELECT DISTINCT (it's more work
> to look for duplicates), VACUUM and VACUUM ANALYZE, etc, etc. The
> default state is to do the least work that makes sense. (There are
> exceptions - UNION ought to be UNION DISTINCT, versus UNION ALL to
> reduce the work done - but this is the general rule.)
>
> Often, a query is done with genuine disregard for order. If you're
> going to take the results of the query and stuff them into a
> hashtable, you don't care what order they come up in. Why have the
> database sort them? Let 'em come in the easiest order possible.
>
> ChrisA
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