On Sun, 16 Sep 2018 13:30:55 +0100 Simon Slavin <slav...@bigfraud.org> wrote:
> On 16 Sep 2018, at 9:29am, John Found <johnfo...@asm32.info> wrote: > > > Is there some relation between the indexes used in the query, the GROUP BY > > fields used > > and the order of the result rows, when no "ORDER BY" clause is used? > > When you ask for GROUP BY, SQLite internally does the same sort of thing as > it does when you ask for ORDER BY. And if you have a useful index then it > will use that index. > > > [...]. So, is it safe to use this implicit ordering, or this behavior can > > be changed in the future versions of SQLite? > > It is not safe. There is nothing in the documentation that says that groups > will be returned in COLLATE order. As you suggest, a future version of > SQLite may choose not to do so. Is it means that in every query that uses GROUP BY and ORDER BY simultaneously, one of the operations will always be provided by using temporary b-tree? > > Simon. > _______________________________________________ > sqlite-users mailing list > sqlite-users@mailinglists.sqlite.org > http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users -- John Found <johnfo...@asm32.info> _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
