GP - Display Active Connections

As a operations person, the 1st and most important thing to check for Active Connections on Database.

Below are SQL(s) which will help in getting Active Connection(s):

1. Show Active Connection(s)
SELECT 
 datname AS "Database",
 procpid AS "Process ID",
 sess_id AS "Session ID",
 usesysid AS "Role OID",
 usename AS " Role Name",
 substr(current_query, 1, 40) AS "Query",
 query_start AS "Query Start Time",
 backend_start AS "Query Backend Start Time",
 (current_timestamp - query_start) AS "Runtime",
 waiting AS "Is Query Waiting on Anything?",
 waiting_reason AS "Reason Query is Waiting"
FROM pg_stat_activity
WHERE procpid != pg_backend_pid()
ORDER BY
 substr(current_query, 1, 40) DESC,
 waiting ASC,
 (current_timestamp - query_start) DESC;
2. If user wants to check for Specific Process ID(s)
SELECT 
 procpid || ':' || usename AS "Process Info",
 current_query AS "Query"
FROM pg_stat_activity
WHERE procpid
IN (procpid#,...);
Above command can be used on individual database too.
psql -d <database_name> -c '<sql>'

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