airflow/models/dag.py
def get_last_dagrun(dag_id, session, include_externally_triggered=False):
    """
    Returns the last dag run for a dag, None if there was none.
    Last dag run can be any type of run eg. scheduled or backfilled.
    Overridden DagRuns are ignored.
    """
    DR = DagRun
    query = session.query(DR).filter(DR.dag_id == dag_id)
    if not include_externally_triggered:
        query = query.filter(DR.external_trigger == False)  # noqa
    query = query.order_by(DR.execution_date.desc())
    return query.first()
def get_last_dagrun(dag_id, session, include_externally_triggered=False):
    """
    Returns the last dag run for a dag, None if there was none.
    Last dag run can be any type of run eg. scheduled or backfilled.
    Overridden DagRuns are ignored.
    """
    DR = DagRun
    query = session.query(DR).filter(DR.dag_id == dag_id)
    if not include_externally_triggered:
        query = query.filter(DR.external_trigger == False)  # noqa
    query = query.order_by(DR.execution_date.desc())
    return query.first()
Returns the last dag run for a dag, None if there was none.
    Last dag run can be any type of run eg. scheduled or backfilled.
    Overridden DagRuns are ignored.