AGE function for differences in PostgreSQL - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to calculate the age difference between two dates using the AGE function.

PostgreSQL

SELECT AGE([1], '2023-01-01') AS difference;

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

A'2021-01-01'

B'2024-01-01'

C'2023-12-31'

D'2022-01-01'

Attempts:

3 left

💡 Hint

Common Mistakes

Using an earlier date as the first argument results in a negative interval.

Forgetting to put the dates in quotes.

The AGE function calculates the interval between two dates. Here, the first argument should be a later date to get a positive difference.

2fill in blank

medium

Complete the code to calculate the age difference between the current date and a given birthdate.

PostgreSQL

SELECT AGE(CURRENT_DATE, [1]) AS age;

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

A'1999-12-31'

B'2025-05-15'

C'2000-05-15'

D'2023-12-31'

Attempts:

3 left

💡 Hint

Common Mistakes

Using a future date as birthdate.

Not using CURRENT_DATE for the current date.

The AGE function here calculates the age from the birthdate to today. The birthdate must be in the past.

3fill in blank

hard

Fix the error in the code to correctly calculate the age difference between two timestamps.

PostgreSQL

SELECT AGE([1], '2023-06-01 12:00:00') AS diff;

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

A'2023-05-31 12:00:00'

B'2023-06-02 12:00:00'

C'2023-06-01 11:00:00'

D'2023-06-01 13:00:00'

Attempts:

3 left

💡 Hint

Common Mistakes

Using an earlier timestamp as the first argument causes negative intervals.

Not including time in the timestamp string.

The AGE function returns the interval between the first and second timestamp. To get a positive difference, the first timestamp should be later.

4fill in blank

hard

Fill both blanks to calculate the age difference between two dates and filter results where the difference is more than 1 year.

PostgreSQL

SELECT AGE([1], [2]) AS age_diff FROM events WHERE AGE([1], [2]) > INTERVAL '1 year';

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

A'2020-01-01'

B'2019-12-31'

C'2021-01-01'

D'2022-01-01'

Attempts:

3 left

💡 Hint

Common Mistakes

Using dates less than a year apart.

Swapping the dates causing negative intervals.

The AGE function calculates the interval between the two dates. Filtering for intervals greater than 1 year requires the dates to be at least one year apart.

5fill in blank

hard

Fill all three blanks to create a query that calculates the age difference between two timestamps, extracts the year part, and filters for differences of 5 years or more.

PostgreSQL

SELECT EXTRACT(year FROM AGE([1], [2])) AS years_diff FROM users WHERE EXTRACT(year FROM AGE([1], [2])) >= [3];

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

A'2015-06-01 08:00:00'

B'2010-06-01 08:00:00'

C5

D10

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping timestamps causing negative intervals.

Using a string instead of a number for the threshold.

Using the wrong EXTRACT field.

The AGE function calculates the interval between two timestamps. EXTRACT(year FROM ...) gets the year part of the interval. Filtering for differences of 5 years or more requires the threshold 5.