-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Griggs, Donald wrote: > Except that the OP wrote: "...I don't think it works very well for 2^32 > possible values (when there may well be only a couple of hundred unused > ones)...."
Sorry, I missed that. > Anyway, Scott has beat me to a suggestion that you could just store the ID > of the *deleted* rows Tracking free space is something all filesystems have to address. The various approaches are: * Store a freelist (which blocks are free) * Store a freelist with extents (list of block runs that are free) * Store a bitmap * Divide the whole space into smaller groups and use one of the first 3 approaches on a group by group basis In general their performance tends to get worse as things get fuller because it takes more work to find a free block. Roger -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEARECAAYFAks79uoACgkQmOOfHg372QThsQCg3T3VvpRYpR0FuQaTwT2wlVDQ K1EAoJJTc8RobyVBSiAuMSz8h4y0KK6K =sCs4 -----END PGP SIGNATURE----- _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
