How to Drop a Database with Active Connections

Posted by Kyle Hankinson March 20, 2025

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Trying to drop a database while other sessions are connected to it will fail. Here is how to terminate those connections and drop the database safely in each database system.

PostgreSQL

The Error

ERROR: database "mydb" is being accessed by other users
DETAIL: There are 3 other sessions using the database.

Solution: Terminate Connections, Then Drop

-- Step 1: Prevent new connections
REVOKE CONNECT ON DATABASE mydb FROM PUBLIC;

-- Step 2: Terminate existing connections
SELECT pg_terminate_backend(pid)
FROM pg_stat_activity
WHERE datname = 'mydb' AND pid <> pg_backend_pid();

-- Step 3: Drop the database
DROP DATABASE mydb;

PostgreSQL 13+: DROP DATABASE FORCE

PostgreSQL 13 added a FORCE option that terminates connections automatically:

DROP DATABASE mydb WITH (FORCE);

This is the simplest approach if you are on PostgreSQL 13 or later.

Checking Active Connections

SELECT pid, usename, application_name, state, query_start
FROM pg_stat_activity
WHERE datname = 'mydb';

SQL Server

The Error

Cannot drop database "mydb" because it is currently in use.

Solution: Set Single User Mode

-- Terminate all connections and switch to single-user mode
ALTER DATABASE mydb SET SINGLE_USER WITH ROLLBACK IMMEDIATE;

-- Drop the database
DROP DATABASE mydb;

WITH ROLLBACK IMMEDIATE rolls back any in-progress transactions and disconnects all users immediately.

Alternative: Kill Connections Manually

-- Find active sessions
SELECT session_id, login_name, status, last_request_start_time
FROM sys.dm_exec_sessions
WHERE database_id = DB_ID('mydb');

-- Kill each one
KILL 52;
KILL 53;

-- Then drop
DROP DATABASE mydb;

MySQL

MySQL is more lenient — DROP DATABASE does not require exclusive access. However, active queries will continue running against the dropped tables until they finish or error out.

To cleanly terminate connections first:

-- Find connections to the database
SELECT ID, USER, HOST, DB, COMMAND, TIME, STATE
FROM INFORMATION_SCHEMA.PROCESSLIST
WHERE DB = 'mydb';

-- Kill each connection
KILL 42;
KILL 43;

-- Drop the database
DROP DATABASE mydb;

Or in MySQL 8.0+:

SELECT CONCAT('KILL ', ID, ';')
FROM INFORMATION_SCHEMA.PROCESSLIST
WHERE DB = 'mydb';

Run the output to kill all connections at once.

Quick Reference

Database	Command
PostgreSQL 13+	DROP DATABASE mydb WITH (FORCE)
PostgreSQL < 13	pg_terminate_backend() then DROP DATABASE
SQL Server	ALTER DATABASE SET SINGLE_USER WITH ROLLBACK IMMEDIATE then DROP
MySQL	KILL connections then DROP DATABASE

Safety Considerations

• Always double-check the database name before dropping. There is no undo.
• In production: Take a backup first. Use pg_dump, mysqldump, or SQL Server backup.
• In CI/CD: The PostgreSQL WITH (FORCE) option is ideal for tearing down test databases.
• Never run these commands against production databases unless you are absolutely certain. A typo in the database name can be catastrophic.

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