cannot drop the currently open database

What it means

Every PostgreSQL session is connected to exactly one database and can’t switch to another. A database can only be dropped when no session is using it, and that includes yours, so PostgreSQL refuses straight away:

ERROR:  cannot drop the currently open database

Nothing was changed. The fix is to run the same command from a session connected to some other database on the same server.

Common causes

1. Dropping from inside it: you connected to shop to look around, then ran DROP DATABASE shop in the same window.
2. A client or script whose connection names the database it’s dropping, such as a reset script using the app’s own DATABASE_URL.
3. A test or setup tool configured with the test database as its maintenance database.

How to fix it

Connect to another database, then drop

Every server has a database called postgres, made for this kind of maintenance:

psql -h <host> -U <user> -d postgres -c 'DROP DATABASE shop'

In psql you can switch first with \c postgres (which opens a new session in postgres), then run DROP DATABASE shop;. Any other database you can connect to works as well.

Or use dropdb

dropdb connects to a maintenance database for you (postgres, or template1 if that fails):

dropdb -h <host> -U <user> shop
dropdb -h <host> -U <user> --force shop   # PostgreSQL 13+: also ends other sessions

If it then says other users are connected

Once you’re not the one using it, other sessions may still be: see database is being accessed by other users.

Not inside a transaction

DROP DATABASE can’t run inside BEGIN … COMMIT either; some tools wrap everything in a transaction, and then the error is DROP DATABASE cannot run inside a transaction block.

Reproduce it

In a throwaway PostgreSQL 18.6 container, connected to a database named shop:

DROP DATABASE shop;
SELECT current_database();

ERROR:  cannot drop the currently open database
 current_database
------------------
 shop
(1 row)

From a session connected to postgres, DROP DATABASE IF EXISTS shop then worked. With \set VERBOSITY verbose, psql shows the code: ERROR: 55006: cannot drop the currently open database.

In Inlet

On connections Inlet protects, a DROP in the query editor asks before it runs and says why. Run the DROP DATABASE from a connection whose database is a different one, such as postgres; when a statement fails, Inlet shows the server’s error, and What this error means opens this page.