code: def tables(self, dbName=None):
          
          if dbName is None:
              return DataFrame(self._ssql_ctx.tables(), self)
          else:
              return DataFrame(self._ssql_ctx.tables(dbName), self)
docs: Returns a :class:`DataFrame` containing names of tables in the given database.
  
          If ``dbName`` is not specified, the current database will be used.
  
          The returned DataFrame has two columns: ``tableName`` and ``isTemporary``
          (a column with :class:`BooleanType` indicating if a table is a temporary one or not).
  
          :param dbName: string, name of the database to use.
          :return: :class:`DataFrame`
  
          >>> sqlContext.registerDataFrameAsTable(df, "table1")
          >>> df2 = sqlContext.tables()
          >>> df2.filter("tableName = 'table1'").first()
          Row(database=u'', tableName=u'table1', isTemporary=True)