Re: same query, two different approaches, vastly different performance
Puneet Kishor <[email protected]>
| Newsgroups | gmane.comp.lang.perl.modules.dbi.general |
|---|---|
| Message-ID | <[email protected]> |
On Feb 13, 2012, at 7:12 PM, Mike Blackwell wrote: > Check the postgres-performance list archives. I believe the difference is due to the query planner having less info available with parameters vs inline args. > ahhhh... that makes sense. I would like to confirm this, because, if true, then it is a strike against statements prepared with bind values. > > > On Feb 13, 2012, at 19:07, Puneet Kishor <[email protected]> wrote: > > > On Feb 13, 2012, at 6:57 PM, David Nicol wrote: > >> did you find >> >> http://stackoverflow.com/questions/1566717/postgresql-like-query-performance-variations >> >> in your research? > > > Thanks for that link, but I don't think that applies in my case. I have two exact queries, with a postfix wildcard search. One, I prepare with the search term embedded in the query. The other is prepared with a bind variable and the search term is added during $sth->execute. > > The first one uses the index. The second does a full-table scan. > > Strange, but true. > > > > -- > Puneet Kishor