On 3 Feb 2011, at 10:43am, Mihai Militaru wrote: > Nicolas Williams <nicolas.willi...@oracle.com> wrote: > >>> Any idea why pg does ok on these queries without the extra index - >>> Maybe they're created by default? SQLIte doesn't create any indexes >>> automatically on primary key fields or anything else, correct? >> >> No, it doesn't. Use EXPLAIN QUERY PLAN to see what SQLite3 is doing. > > Hmm SqLite does create persistent indices on UNIQUE - and consequently > PRIMARY - keys, doesn't it?
SQLite creates some indexes the programmer doesn't specifically ask for: on the rowid, on the primary key, and on any column declared as UNIQUE. Of course, in a particular table all three of these might actually be the same column, so it might need just one. But every table has at least one index. Simon. _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
