Btw... does this 'one index' also include indexes used for joining? Thanks Ray
Raeldor wrote: > > Hi, > > Seriously... it can only use one index per query? I tried your union > suggestion and it works well, thank you. I had no idea it was limited to > a single index. > > Thanks > Ray > > > Griggs, Donald-3 wrote: >> >> Regarding: >> select * from table1 where field1='x' or field2='y' >> >> >> Hi, Ray, >> >> I believe you sent two messages -- the first with "OR" and the second >> with "AND". >> >> Since your subject consistently says "OR" and your last email says "AND" >> I'll assume you meant "AND". >> >> >> Sqlite using a maximum of one index per table per select. >> >> In order to perform your "OR" select, it must scan every the table. >> >> You may want to create a compound index of both fields. >> >> (Or maybe a "UNION ALL" would be fast? You can use EXPLAIN QUERY PLAN to >> analyze.) >> >> >> Hope this helps, >> Donald >> _______________________________________________ >> sqlite-users mailing list >> sqlite-users@sqlite.org >> http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users >> >> > > -- View this message in context: http://old.nabble.com/Very-Odd...-where-field1%3D%27%27-or-field2%3D%27%27-is-slow-tp28491829p28492106.html Sent from the SQLite mailing list archive at Nabble.com. _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
