How to rename database with active sessions

Useful when you need to for example switch databases – you must do it from psql when connected to other database (db postgres is the best choice in this case):

• restrict further connections into this database:
  • ALTER DATABASE your_old_database CONNECTION LIMIT 0;
• close existing sessions with:
  • select pg_terminate_backend(procpid) from pg_stat_activity where datname = ‘your_old_database’ and procpid <> pg_backend_pid();
• rename old to different name
• rename new to proper name
• allow connections on old database:
  • ALTER DATABASE your_old_renamed_database CONNECTION LIMIT -1;