Dave Cramer <pg@fastcrypt.com> writes:
> create index r_url_idx on url( fn_strrev(url));
> explain select * from url where url like fn_strrev('%beta12.html');
> QUERY PLAN
> ---------------------------------------------------------
> Seq Scan on url (cost=0.00..13281.70 rows=1 width=454)
> Filter: ((url)::text ~~ 'lmth.21ateb%'::text)
> Is it possible to get the planner to use an index scan ?
Sure, but not that way. Try "fn_strrev(url) like something".
You have to compare the indexed value to something...
regards, tom lane
