Use of indexes in plpgsql functions

> I have a table with 650k rows with an index on URL (pg v7.0.0 on
> i686-pc-linux-gnu)
>
> When using psql the select query behaves as expected i.e. takes < 1 second
> (and explain tells me it is using the correct index)
>
> However when I put this into a pl function it takes about 2.5 mins, Has
> anyone had any similar problems/solutions or is it just that I am over
> looking something??? (I know there is an update but again when executed
> seperately it takes approx 1 sec)
>
> Regards
>
> Graham
>
> details as follows: -
>
> SELECT now(); SELECT count(*) FROM statistics WHERE url ='XXX' and
> website_id =1035; SELECT now();
>
> now
> ----------------------
> 2000-12-15 19:17:34+00
>
> count
> -----
>     421
> (1 row)
>
> now
> ----------------------
> 2000-12-15 19:17:35+00
> (1 row)
>
> CREATE FUNCTION get_url_hits (varchar, int4) RETURNS int4 AS '
> DECLARE
>     num INT4;
> BEGIN
>     SELECT count(*) INTO num FROM statistics WHERE url = $1 and
> website_id = $2;
>
>     IF num > 0 THEN
>         UPDATE site_url SET hits = num, last_updated = now() where
> website_id = $2 and url = $1;
>     END IF;
> RETURN num;
> END;' LANGUAGE 'plpgsql';
>
> select now(); select get_url_hits ('XXX', 1001); select now();
>
> now
> ----------------------
> 2000-12-15 19:21:40+00
> (1 row)
>
> get_url_hits
> ------------
>       421
> (1 row)
>
> now
> ----------------------
> 2000-12-15 19:24:06+00
> (1 row)
>
>
>
>
>
>