Re: performance issue
От | Kris Jurka |
---|---|
Тема | Re: performance issue |
Дата | |
Msg-id | 47EB2E81.3080302@ejurka.com обсуждение исходный текст |
Ответ на | performance issue (Steven varga <varga@yorku.ca>) |
Ответы |
Re: performance issue
|
Список | pgsql-jdbc |
Steven varga wrote: > > having about 10^6 records in a table indexed on names and doing a > query from psql I get response time in millisec order on the other > hand when executing the same query through JDBC it hangs about 80 > seconds. > > PreparedStatement count = > connection.prepareStatement("SELECT count(*) FROM > upc WHERE name like upper(?)||'%' "); > When using a PreparedStatement the server must come up with a plan that works for all parameter values. Since the parameter is unknown, the generated plan doesn't use an index. Your options are to interpolate the parameter yourself or connect using the protocolVersion=2 URL option which will make the driver do the interpolation prior to passing the query on to the server. Kris Jurka
В списке pgsql-jdbc по дате отправления: