On 7 May 2014, at 1:29pm, Woody Wu <narkewo...@gmail.com> wrote: > The 'explain query plan' gives same result for the first and the second query: > > 0|0|0|SEARCH TAB mp USING COVERING INDEX sqlite_auto_index_mp_1 (ntimereq<?) > (~1 rows) > > BTW: I dont understand what the (~1 rows) mean.
Literally "about 1 row". This is SQLite's estimate of how many rows the 'mp' table has. You can let SQLite make a better estimate by using the 'ANALYZE' command. It doesn't matter for this particular SELECT but for complicated SELECT commands which involve searching more than one table, knowing how long each table is and how it's indexed can help SQLite choose a good search strategy. And now back to someone else who might be able to help you understand your original problem. Simon. _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
