def create_index_sql(self, table_name, column_names, unique=False, db_tablespace=''):
        if not column_names:
            print("No column names supplied on which to create an index")
            return ''

        connection = self._get_connection()
        if db_tablespace and connection.features.supports_tablespaces:
            tablespace_sql = ' ' + connection.ops.tablespace_sql(db_tablespace)
        else:
            tablespace_sql = ''

        index_name = self.create_index_name(table_name, column_names)
        return 'CREATE %sINDEX %s ON %s (%s)%s;' % (
            unique and 'UNIQUE ' or '',
            self.quote_name(index_name),
            self.quote_name(table_name),
            ','.join([self.quote_name(field) for field in column_names]),
            tablespace_sql
        )
Generates a create index statement on 'table_name' for a list of 'column_names'
dataset/ETHPy150Open cloudera/hue/desktop/core/ext-py/South-1.0.2/south/db/generic.py/DatabaseOperations.create_index_sql