On Mon, Oct 4, 2010 at 1:53 AM, Roger Binns <rog...@rogerbinns.com> wrote:
> -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > On 10/03/2010 10:01 PM, Max Vlasov wrote: > > On Sun, Oct 3, 2010 at 7:21 PM, Roger Binns <rog...@rogerbinns.com> > wrote: > > > >> > >> Also note that xTruncate may be called to make a file longer. > >> > >> > > Roger, are you sure about that? > > That has certainly been stated in the past. Unfortunately the current > io_methods documentation doesn't say anything about xTruncate. > > Looking through the source, the vast majority of cases would indeed result > in a shorter file with writes used to extend. But there may be lengthening > from walCheckpoint() and possibly as part of the backup process. > > In any event unless there is an explicit guarantee from the SQLite authors > that xTruncate will never be called to lengthen a file (including in future > versions) then it should be something that should be checked for and > errored > or implemented as appropriate. > I'm not willing to say we will support this forever, but recent versions of SQLite do work correctly if xTruncate is a no-op. I think the support for this began with version 3.7.0. If xTruncate is a no-op, then the VACUUM command will not actually reduce the size of the database file, of course. But everything else should work as expected. The xTruncate=noop support was added for a popular consumer gadget that uses SQLite on an operating system that does not support file truncation. > > Roger > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v1.4.10 (GNU/Linux) > Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ > > iEYEARECAAYFAkypa/EACgkQmOOfHg372QRugwCguKqqfXhf2+/jrwDYnYwid7CY > mjkAn1JnTYIhlKey7YW6QumIWe4oLwJR > =5hwL > -----END PGP SIGNATURE----- > _______________________________________________ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > -- D. Richard Hipp d...@sqlite.org _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
