PostgreSQL 11 Administration Cookbook

How it works…

Suppose you change the value of a setting during your session, for example, by issuing this command:

SET work_mem = '16MB';

Then, the following will show up in the pg_settings catalog view:

postgres=# SELECT name, setting, reset_val, source FROM pg_settings WHERE source = 'session';     name   | setting | reset_val | source   ----------+---------+-----------+---------  work_mem | 16384   | 4096      | session

This will show until you issue this command:

RESET work_mem;

After issuing it, the setting returns to reset_val and the source returns to the default:

 name   | setting | reset_val | source   ---------+---------+-----------+--------- work_mem | 4096    | 4096      | default