If you want more precise timings then turn on log_duration_statement. The logs will carry timings down to the microsecond.
Also note that this is not the correct list for such questions - this list is about development of PostgreSQL, not use.
cheers andrew Kenneth Marshall wrote:
Mickael, Not knowing your query, it sounds like your method is working correctly. It is quite normal to have the initial query take longer than subsequent queries. This is a cache effect and is what databases, in general, strive for performance-wise. I suspect that the second time you run the query that it does not take 0ms, just less than 1ms. Ken On Sat, Jul 21, 2007 at 03:26:19PM +0200, Mickael DELOISON wrote:Hello, I am trying to get the execution time of a query by using JDBC (Java). To do that I make the difference between the time (in milliseconds) after the query execution and the time before the query execution. The first time I do that, I get the real execution time, but the query plan seems to be cached. And the next time I do the same operation, for a simple query I do not get the real time (in fact my 'simple' query seems to execute in 0 millisecond). So I need help: I would like to solve this problem but I do not know how. I have tried some researches on Internet but I did not find. Is there a possibility to disable the query plan cache temporarily? It is also possible I am totally wrong and the problem is not where I see it... Anyway I need help. Thank you in advance, Mickael ---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match---------------------------(end of broadcast)--------------------------- TIP 5: don't forget to increase your free space map settings
---------------------------(end of broadcast)--------------------------- TIP 2: Don't 'kill -9' the postmaster
