Re: query_id: jumble names of temp tables for better pg_stat_statement UX

Hi,

I totally understand the wish to make pg_stat_statements useful for
workloads that create/drop a ton of temporary tables.
However, when pursuing this goal we impacted other types of totally valid
workloads when tables with the same name exist in different schemas.
Example:
create schema s1;
create table s1.t as select id from generate_series(1, 10) as id;
create schema s2;
create table s1.t as select id from generate_series(1, 1000000) as id;
select count(id) from s1.t;
select count(id) from s2.t;

select * from pg_stat_statements;
userid | 10
dbid | 5
toplevel | t
queryid | -8317141500049987426
query | select count(id) from s1.t
plans | 0
total_plan_time | 0
min_plan_time | 0
max_plan_time | 0
mean_plan_time | 0
stddev_plan_time | 0
calls | 2
total_exec_time | 22.577107
min_exec_time | 0.325021
max_exec_time | 22.252086000000002
mean_exec_time | 11.2885535
stddev_exec_time | 10.963532500000001
rows | 2
shared_blks_hit | 4425

That is, two different queries, accessing two absolutely different tables
(one of them has 100000 times more rows!) were merged together.

Regards,
--
Alexander Kukushkin