How do I drop or create a database from clojure.java.jdbc?

Take the source for do-commands (here) and remove the call to transaction:

(defn drop-database [name]
  (sql/with-connection db
    (with-open [s (.createStatement (sql/connection))]
      (.addBatch s (str "drop database " name))
      (seq (.executeBatch s)))))

The transactionless execution functionality was rolled into db-do-commands.

Now this slightly simpler version is working:

(jdbc/db-do-commands postgres-db false "CREATE DATABASE foo")

If you don't specify false as the second argument, it won't work as it will attempt to start a transaction.