We are seeing a quite heavy slow down when using prepared statements in 10.1. I haven't done some thorough testing, to be honest, but what we are having is a select from a view (complexity of it should not matter in my opinion), something like this: prepare TEST (text, int) select * from OUR_VIEW where COLUMNA = $1 and COLUMNB = $2; -- Actual test code follows. -- Takes ~2 seconds. select * from OUR_VIEW where COLUMNA = 'N' and COLUMNB = 35; -- Takes ~10 seconds. execute TEST ('N', 35); Both return the same amount of rows, order of execution does not matter, these times are reproducible. If the same select statement is executed through JDBC it takes roughly 6 seconds (execution time only, no data fetched at that point). I'm a little bit at a loss here. Is such a slow down "expected", did we simply miss that prepared statements are slower? Or is there something else going on that we are simply not aware of?