Jens Alfke <j...@mooseyard.com> wrote: > In a simple SELECT query of a single table, using the C API, > is there any difference in performance for requesting more or > fewer columns of the table in the result? Or is the performance > penalty only incurred when actually reading the column values?
There can sometimes be a big difference. The less columns you select, the more chance you have to be able to use a covering index. If the query can use a covering index, it's likely to have a significant speed up. According to section 8.0 at https://www.sqlite.org/optoverview.html being able to use a covering index makes the query about twice as fast. Regards Dominique _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
