CURRENT_SETTING

Return the current setting of a specific configuration parameter.
CURRENT_SETTING('parameter')
For example:
premdb_utf8=# set application_name='YBSQL_CLIENT';
SET
premdb_utf8=# select current_setting('application_name');
 current_setting 
-----------------
 YBSQL_CLIENT
(1 row)

premdb_utf8=# select current_setting('search_path') from sys.const;
      current_setting      
---------------------------
 public,premdb_tables,bobr
(1 row)

See also SHOW.