Dumps current database schema.

def DumpCurrentSchema(cursor):
  """Dumps current database schema."""
  cursor.execute("SELECT TABLE_NAME FROM INFORMATION_SCHEMA.TABLES "
                 "WHERE table_schema = (SELECT DATABASE())")
  defs = []
  for table, in sorted(cursor.fetchall()):
    cursor.execute("SHOW CREATE TABLE `{}`".format(table))
    rows = cursor.fetchall()
    defs.append(rows[0][1])

  return "\n\n".join(defs)