log_planner_stats and prepared statements
I have found that log_planner_stats only outputs stats until the generic
plan is chosen. For example, if you run the following commands:
SET client_min_messages = 'log';
SET log_planner_stats = TRUE;
PREPARE e AS SELECT relkind FROM pg_class WHERE relname = $1 ORDER BY 1;
EXPLAIN ANALYZE VERBOSE EXECUTE e ('pg_class');
EXPLAIN ANALYZE VERBOSE EXECUTE e ('pg_class');
EXPLAIN ANALYZE VERBOSE EXECUTE e ('pg_class');
EXPLAIN ANALYZE VERBOSE EXECUTE e ('pg_class');
EXPLAIN ANALYZE VERBOSE EXECUTE e ('pg_class');
EXPLAIN ANALYZE VERBOSE EXECUTE e ('pg_class');
--> EXPLAIN ANALYZE VERBOSE EXECUTE e ('pg_class');
The last explain will _not_ show any log_planner_stats duration, though
it does show an EXPLAIN planning time:
Planning Time: 0.012 ms
It this expected behavior?
--
Bruce Momjian <bruce@momjian.us> http://momjian.us
EnterpriseDB http://enterprisedb.com
+ As you are, so once was I. As I am, so you will be. +
+ Ancient Roman grave inscription +
Bruce Momjian <bruce@momjian.us> writes:
I have found that log_planner_stats only outputs stats until the generic
plan is chosen. For example, if you run the following commands:
Uh, well, the planner doesn't get run after that point ...
regards, tom lane
On Wed, Apr 17, 2019 at 12:04:35AM -0400, Tom Lane wrote:
Bruce Momjian <bruce@momjian.us> writes:
I have found that log_planner_stats only outputs stats until the generic
plan is chosen. For example, if you run the following commands:Uh, well, the planner doesn't get run after that point ...
Yes, that was my analysis too, but EXPLAIN still prints a planner line,
with a duration:
Planning Time: 0.674 ms
Planning Time: 0.240 ms
Planning Time: 0.186 ms
Planning Time: 0.158 ms
Planning Time: 0.159 ms
Planning Time: 0.169 ms
--> Planning Time: 0.012 ms
Is that consistent? I just don't know. What is that line measuring?
--
Bruce Momjian <bruce@momjian.us> http://momjian.us
EnterpriseDB http://enterprisedb.com
+ As you are, so once was I. As I am, so you will be. +
+ Ancient Roman grave inscription +