psql drop database with connections code example

Example 1: postgres killing connections on db

SELECT 
    pg_terminate_backend(pid) 
FROM 
    pg_stat_activity 
WHERE 
    -- don't kill my own connection!
    pid <> pg_backend_pid()
    -- don't kill the connections to other databases
    AND datname = 'database_name'
    ;

Example 2: drop database using terminal postgres

sql -U <user>  -c "drop database protodb"