Won't work unfortunately. Currently indices are never used if
the WHERE clause has an OR expression in it.
--- Aaron Burghardt <[EMAIL PROTECTED]> wrote:
> Try adding another index:
>
> CREATE INDEX a_f1_f2 ON a (f1, f2);
>
> Does that help?
>
> Aaron Burghardt
>
> On Jul 11, 2005, at 6:07 AM, Ben Clewett wrote:
>
>
> > Dear SQLite,
> >
> > I have found a possible area where the SQL logic of SQLite is not
> > as good as other DBMS. Like MySQL or PostgreSQL. It's a simple
> > thing, so I am showing it as a candidate for work. (If I could
> > submit a patch I would :)
> >
> > If you create a table with two indexes:
> >
> > CREATE TABLE a (
> > f0 INTEGER PRIMARY KEY,
> > f1 INTEGER,
> > f2 INTEGER
> > );
> > CREATE INDEX a_f1 ON a (f1);
> > CREATE INDEX a_f2 ON a (f2);
> >
> > Now execute a query using both the indexes:
> >
> > SELECT * FROM a WHERE f1 = 1 OR f2 = 1;
> >
> > This query will not use the indexes. The query will increment
> > through every row in the table. This is obviously very slow.
> >
> > As I mensioned, MySQL and PostgreSQL will use the indexes here, and
> > therefore return the result considerably faster.
> >
> > I can use the 'UNION' to get the result I am after, so it's not a
> > show stopper.
> >
> > I hope this is of interest to somebody.
> >
> > Regards,
> >
> > Ben Clewett.
> >
> >
> >
> >
> >
> >
>
>
>
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