Well, then you're handcuffing it when an index would be better but is in 
nowhere near rowid order.


-----Original Message-----
From: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] On 
Behalf Of Bart Smissaert
Sent: Thursday, January 12, 2017 3:53 PM
To: General Discussion of SQLite Database
Subject: Re: [sqlite] Why this query plan?

How about a
pragma_sort_asc_on_rowid_or_primary_integer_key_for_unordered_selects ?

RBS

On 12 Jan 2017 20:35, "Richard Hipp" <d...@sqlite.org> wrote:

> On 1/12/17, David Raymond <david.raym...@tomtom.com> wrote:
> >
> > In the same vane I assume DRH's random ordering would be only random by
> page
> > of results. If you have 100+ million records in a table then keeping
> track
> > of which ones you've randomly picked so far would cripple systems with
> the
> > tracking requirements and with the slowdown of skipping all over the
> file.
> > Shuffling the order is one thing, killing performance is another.
> >
>
> The idea is that as each new database connection is opened, the
> reversed_unordered_selects pragma
> (https://www.sqlite.org/pragma.html#pragma_reverse_unordered_selects)
> would be enabled or disabled at random.  That means that results might
> be backwards from one run to the next, but within the same run they
> would always be the same.  That is not really "random" but I think it
> should be sufficient to find instances of omitted ORDER BY clauses, at
> least for the case where the developers test their application more
> than once or twice.
> --
> D. Richard Hipp
> d...@sqlite.org
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