def visit_create_database(self, tokens, running_scheme):
    if running_scheme and self._GetDescendants(running_scheme, 'shard'):
      self.AddError(tokens, 'CREATE should be run on all shards')
    db = self._GetDescendants(tokens, 'database')[0][0]
    try:
      db = self._db_schema.FindDatabase(db)
      self.AddError(tokens, 'Database %s already exists' % db)
    except schema.UnknownNameException:
      self._db_schema.AddDatabase(db)
dataset/ETHPy150Open google/mysql-tools/parser_lib/validator.py/CreateDatabaseChecker.visit_create_database/original