ok, thank you for the advices, I'll try to use a TRIGGER. The DB already has an index. Anyway if I have to count something like this: select COUNT(*) from logs WHERE DateTime<=yesterday I can't do it with a TRIGGER
Il 24/09/2010 10.29, Martin Engelschalk ha scritto: > Hello Michele, > > sqlite does not remember the number of records in a table. Therefore, > counting them requires to scan the full table, which explains the slow > perfornamce. > > This topic has been discussed previously in this list. See > http://www.mail-archive.com/sqlite-users@sqlite.org/msg10279.html > > If you need the result quickly, you have to maintain the rnumber of > records yourself in a different table, perhaps using triggers. > > Martin > > > Am 24.09.2010 10:13, schrieb Michele Pradella: >> I have an SQLite DB of about 9GB with about 2.500.000 records. >> I can't understand why the "select COUNT(*) from log" statement is >> extremely slow, it takes me about 9-10 minutes! >> I try with: >> select COUNT(1) from logs >> select COUNT(DateTime) from logs >> same result. Have you idea of why it's so slow? >> _______________________________________________ >> 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 > > -- Selea s.r.l. Michele Pradella R&D SELEA s.r.l. Via Aldo Moro 69 Italy - 46019 Cicognara (MN) Tel +39 0375 889091 Fax +39 0375 889080 *michele.prade...@selea.com* <mailto:michele.prade...@selea.com> *http://www.selea.com* _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
