Thank you for clarification. I'll forward this to the original reporter and add a note about this to our library.
Regards, Kenichi Ishigaki 2013/4/14 Jay A. Kreibich <j...@kreibi.ch>: > On Sat, Apr 13, 2013 at 11:25:41PM +0700, Dan Kennedy scratched on the wall: >> On 04/13/2013 11:22 PM, kenichi ishigaki wrote: >> >Hi. >> > >> >I received a report that the result of the following SQL has changed >> >since 3.7.15. >> >I haven't looked into the sqlite source yet, but can we call this a bug? >> >> No. No "ORDER BY" clause means that the results are delivered in >> an undefined order. So both results are the same. > > In fact, SQLite has a "PRAGMA reverse_unordered_selects" configuration > that changes the default ordering. This specifically exists to test > applications and make sure they don't assume a specific ordering in > queries that lack an ORDER BY clause. > > You might consider this to test other areas of your application. > > > http://sqlite.org/pragma.html#pragma_reverse_unordered_selects > > When enabled, this PRAGMA causes SELECT statements without an ORDER > BY clause to emit their results in the reverse order of what they > normally would. This can help debug applications that are making > invalid assumptions about the result order. > > SQLite makes no guarantees about the order of results if a SELECT > omits the ORDER BY clause. Even so, the order of results does not > change from one run to the next, and so many applications > mistakenly come to depend on the arbitrary output order whatever > that order happens to be. However, sometimes new versions of SQLite > will contain optimizer enhancements that will cause the output > order of queries without ORDER BY clauses to shift. When that > happens, applications that depend on a certain output order might > malfunction. By running the application multiple times with this > pragma both disabled and enabled, cases where the application makes > faulty assumptions about output order can be identified and fixed > early, reducing problems that might be caused by linking against a > different version of SQLite. > > > > -j > > -- > Jay A. Kreibich < J A Y @ K R E I B I.C H > > > "Intelligence is like underwear: it is important that you have it, > but showing it to the wrong people has the tendency to make them > feel uncomfortable." -- Angela Johnson > _______________________________________________ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
