from airflow import DAG
from datetime import datetime, timedelta
from airflow.operators.postgres_operator import PostgresOperator

default_args = {
    'owner': 'airflow',
    'depends_on_past': False,
    'start_date': datetime(2019, 8, 25),
    'email_on_failure': False,
    'email_on_retry': False,
    'retries': 1,
    'retry_delay': timedelta(minutes=5),
}

with DAG('example_dag',
            max_active_runs=3,
            schedule_interval='@daily',
            default_args=default_args) as dag:

    t1 = PostgresOperator(
        task_id='my_task',
        sql='sql/my_query.sql'
    )