On 2 Sep 2013, at 3:58pm, Bert Huijben <rhuij...@apache.org> wrote: > We anticipate that the wc_id column will be used more in future versions and > I had hoped that the assumption that a better index match (matching more > usable columns) would always be preferable over one that uses less columns.
If you want to test for good indexes and don't understand how indexing will work on your data ... 1) Put in a convincing set of data 2) Run ANALYZE 3) Make up a ton of indexes, indexing lots of tables in many different orders. 4) Find the SELECT and UPDATEs you run most often and use EXPLAIN QUERY PLAN on them. 5) Keep the indexes the query plans mention, and drop the ones they don't mention. This stuff can't be done by theory: there are too many possibilities and it requires too good an understanding of how the query planner works for non-experts. There's no substitute for actual testing. Simon. _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
