On Thu, Nov 8, 2012 at 05:37:22PM -0800, Tianyin Xu wrote: > Thanks, Craig, > > Yes, I know "context diff". What I don't know is whether + or - some rows is a > big problem, let's say correctness problem. I didn't write the test cases so I > don't know what these test cases are exactly doing. > If you tell me the failure of these test cases are severe and not acceptable, > I'm fine with it. It means these configurations are not allowed. > > For this particular case, I figured out that it's because of the following > settings, > > cpu_index_tuple_cost = 2147483647 > > which assigned a big number to the cpu_index_tuple_cost, affecting the query > planner. > > But to me, the configuration settings should not affect the correctness, right? > Because whatever optimizations you do, the results should be the same (what > matters is the performance). And that's why I need testing before adjusting > these values. We can't test the optimizer is reasonable if you change settings in this way, so no, I am not surprised it failed. -- Bruce Momjian <bruce@xxxxxxxxxx> http://momjian.us EnterpriseDB http://enterprisedb.com + It's impossible for everything to be true. + -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
