orm.py 文件源码

def validate_in_transaction(connection):
    """Ensure that `connection` is within a transaction.

    This only enquires as to Django's perspective on the situation. It does
    not actually check that the database agrees with Django.

    :raise TransactionManagementError: If no transaction is in progress.
    """
    if not in_transaction(connection):
        raise TransactionManagementError(
            # XXX: GavinPanella 2015-08-07 bug=1482563: This error message is
            # specific to lobjects, but this lives in a general utils module.
            "PostgreSQL's large object support demands that all interactions "
            "are done in a transaction. Further, lobject() has been known to "
            "segfault when used outside of a transaction. This assertion has "
            "prevented the use of lobject() outside of a transaction. Please "
            "investigate.")