Cron expressions in Airflow - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to schedule a DAG to run every day at midnight using a cron expression.

Apache Airflow

schedule_interval = '[1]'

Drag options to blanks, or click blank then click option'

A0 0 * * *

B0 12 * * *

C* * * * *

D0 0 * * 0

Attempts:

3 left

💡 Hint

Common Mistakes

Using 12 instead of 0 for hour to represent midnight.

Using '*' for hour which means every hour.

The cron expression 0 0 * * * means the task runs daily at midnight (00:00).

2fill in blank

medium

Complete the code to schedule a DAG to run every Monday at 6 AM.

Apache Airflow

schedule_interval = '[1]'

Drag options to blanks, or click blank then click option'

A0 18 * * 1

B0 6 * * 0

C0 6 * * 1

D0 6 1 * *

Attempts:

3 left

💡 Hint

Common Mistakes

Using 0 for Monday instead of 1.

Using 18 for hour which means 6 PM instead of 6 AM.

The cron expression 0 6 * * 1 means the task runs at 6:00 AM every Monday (day 1 of the week).

3fill in blank

hard

Fix the error in the cron expression to run a DAG every 15 minutes.

Apache Airflow

schedule_interval = '[1]'

Drag options to blanks, or click blank then click option'

A*/15 * * * *

B15 * * * *

C0/15 * * * *

D0 * * * */15

Attempts:

3 left

💡 Hint

Common Mistakes

Using '15 * * * *' which runs only at minute 15 every hour.

Using '0/15' which is not standard cron syntax.

The correct cron expression for every 15 minutes is */15 * * * *. It means every 15 minutes at any hour, day, month, and weekday.

4fill in blank

hard

Fill both blanks to schedule a DAG to run at 3:30 PM on the 1st day of every month.

Apache Airflow

schedule_interval = '[1] [2] 1 * *'

Drag options to blanks, or click blank then click option'

A30

B15

C3

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping hour and minute fields.

Using 3 instead of 15 for hour which is 3 AM, not 3 PM.

The minute field should be 30 and the hour field 15 (3 PM in 24-hour format). The rest means every 1st day of the month.

5fill in blank

hard

Fill all three blanks to schedule a DAG to run every weekday at 8:00 AM.

Apache Airflow

schedule_interval = '[1] [2] * * [3]'

Drag options to blanks, or click blank then click option'

A0

B8

C1-5

D0-6

Attempts:

3 left

💡 Hint

Common Mistakes

Using 0-6 for day of week which includes weekends.

Swapping hour and minute fields.

The minute is 0, hour is 8 (8 AM), and day of week is 1-5 which means Monday to Friday (weekdays).