Check Who's Logged In: Methods for Finding Connected Users in PostgreSQL

1. Check the Current User:

This is the simplest method. You can use the current_user function inside psql to see the user you're currently connected as. Just type select current_user; in the psql prompt.

1. View All Active Users:

PostgreSQL offers a system view named pg_stat_activity. This view provides information about current activities on the server, including connected users. To see all active users, run the following query:

SELECT usename, datname, state
FROM pg_stat_activity;

This will return details like username, database they're connected to (datname), and their current state (idle, active query, etc.).

SELECT current_user;

This will display the username you're currently connected with.

Viewing All Active Users (assuming you have permissions to access pg_stat_activity):

SELECT usename, datname, state
FROM pg_stat_activity;

This code retrieves information about all active users, including:

• username: The username of the connected user.
• datname: The database name the user is connected to (if any).
• state: The current state of the user's connection (e.g., idle, active, waiting).

1. Using pgAdmin (GUI tool):

If you're using a graphical user interface (GUI) tool like pgAdmin to manage your PostgreSQL server, you can view active connections. Here's a general outline:

• Connect to your PostgreSQL server using pgAdmin.
• In the object browser, navigate to the server you're interested in.
• Look for a tab or section labeled "Server Activity" or similar. This will display details about active connections, including usernames and their actions.

1. Operating System Tools:

Depending on your operating system, you might be able to use tools to identify active connections to the PostgreSQL server process. These tools typically won't provide user names directly, but they can show details like client IP addresses or PIDs (process IDs). You might need to combine this information with other methods (like checking pg_stat_activity for usernames on specific PIDs) to identify the users.