same query in high number of times

Hey folks !


Still kind of analyzing the situation , I realized that I do have a reasonably high shared_memory and effective_cache_size , though if the same query is being run in a number of times ~100-200 concurrent connection it is not being cached .

Should PG realize that if the table data is same should the query result set also be the same ? Instead each query takes up to 1-2 seconds .

Where do I see what the PG does ? I can see now the query's that take long time ,but do not have information about what the optimizer does neither when the DB decides about to table scan or cache ?

cheers,
Peter