Hi Craig, The log is really long, but I compared the result of "explain analyze" for first and later executions, except for 3 "time=XXX" numbers, they are identical. I agree with you that PostgreSQL is doing different level of caching, I just wonder if there is any way to speed up PostgreSQL in this scenario, which is a wrong way perhaps. Thank you. Ning On Wed, Jul 15, 2009 at 5:27 PM, Craig Ringer<craig@xxxxxxxxxxxxxxxxxxxxx> wrote: > On Wed, 2009-07-15 at 12:10 +0900, ning wrote: > >> First execution: PostgreSQL 0.006277 seconds / DB2 0.009028 seconds >> Second execution: PostgreSQL 0.005932 seconds / DB2 0.000332 seconds > > Actually, on second thoughts that looks a lot like DB2 is caching the > query results and is just returning the cached results when you repeat > the query. > > I'm not sure to what extent PostgreSQL is capable of result caching, but > I'd be surprised if it could do as much as DB2. > > -- > Craig Ringer > > -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
