DATE arithmetic (DATEDIFF, DATE_ADD) in SQL - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to find the number of days between two dates.

SQL

SELECT DATEDIFF([1], '2024-01-01') AS days_diff;

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

A'2023-12-31'

B'2024-01-10'

C'2024-02-01'

D'2024-01-01'

Attempts:

3 left

💡 Hint

Common Mistakes

Using the dates in the wrong order, which changes the sign of the result.

Using a date format not recognized by SQL.

The DATEDIFF function calculates the difference in days between two dates. Here, we find days between '2024-01-10' and '2024-01-01', which is 9 days.

2fill in blank

medium

Complete the code to add 7 days to a given date.

SQL

SELECT DATE_ADD('2024-03-01', INTERVAL [1] DAY) AS new_date;

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

A1

B0

C7

D30

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong interval unit like MONTH instead of DAY.

Adding zero days which returns the same date.

The DATE_ADD function adds a specified interval to a date. Adding 7 days to '2024-03-01' results in '2024-03-08'.

3fill in blank

hard

Fix the error in the code to subtract 10 days from a date.

SQL

SELECT DATE_ADD('2024-05-15', INTERVAL [1] DAY) AS new_date;

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

A-10

B10

CDAY -10

DINTERVAL -10 DAY

Attempts:

3 left

💡 Hint

Common Mistakes

Putting the negative sign outside the INTERVAL keyword.

Using incorrect syntax like 'DAY -10'.

To subtract days using DATE_ADD, use a negative number in the INTERVAL. So, INTERVAL -10 DAY subtracts 10 days.

4fill in blank

hard

Fill both blanks to calculate the difference in days between two dates stored in columns.

SQL

SELECT DATEDIFF([1], [2]) AS days_between FROM orders;

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Aorder_date

Bdelivery_date

C'2024-01-01'

D'2024-12-31'

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping the columns and getting negative results.

Using fixed dates instead of column names.

To find how many days passed from order to delivery, subtract order_date from delivery_date. So, DATEDIFF(delivery_date, order_date).

5fill in blank

hard

Fill all three blanks to create a dictionary of event names and their day differences from today.

SQL

SELECT JSON_OBJECT([1], DATEDIFF([2], CURRENT_DATE)) AS days_diff FROM events WHERE [3] > CURRENT_DATE;

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

Aevent_date

Devent_name

Attempts:

3 left

💡 Hint

Common Mistakes

Using the same column for key and filter incorrectly.

Not filtering future dates properly.

This query selects event names as keys and calculates days until the event by subtracting current date from event_date. It filters future events only.