Running totals with SUM OVER in SQL - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to calculate a running total of sales ordered by date.

SQL

SELECT date, sales, SUM(sales) OVER (ORDER BY [1]) AS running_total FROM sales_data;

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

Aregion

Bsales

Ccustomer_id

Ddate

Attempts:

3 left

💡 Hint

Common Mistakes

Ordering by sales instead of date causes incorrect running totals.

Using a column unrelated to time order breaks the running total logic.

The running total should be ordered by the date column to accumulate sales over time.

2fill in blank

medium

Complete the code to reset the running total for each region.

SQL

SELECT region, date, sales, SUM(sales) OVER (PARTITION BY [1] ORDER BY date) AS running_total FROM sales_data;

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

Aregion

Bdate

Csales

Dcustomer_id

Attempts:

3 left

💡 Hint

Common Mistakes

Partitioning by date resets the total every day, not by region.

Not using PARTITION BY causes a running total over all data.

Partitioning by region resets the running total for each region separately.

3fill in blank

hard

Fix the error in the code to correctly calculate the running total of sales per customer ordered by date.

SQL

SELECT customer_id, date, sales, SUM(sales) OVER (PARTITION BY customer_id ORDER BY [1]) AS running_total FROM sales_data;

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

Adate

Bsales

Cregion

Dcustomer_id

Attempts:

3 left

💡 Hint

Common Mistakes

Ordering by sales causes running totals to jump incorrectly.

Ordering by customer_id inside partition by customer_id is redundant and wrong.

The running total must be ordered by date to accumulate sales chronologically per customer.

4fill in blank

hard

Fill both blanks to calculate a running total of sales per region, ordered by date, and include only sales greater than 100.

SQL

SELECT region, date, sales, SUM(sales) OVER (PARTITION BY [1] ORDER BY [2]) AS running_total FROM sales_data WHERE sales > 100;

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

Aregion

Bdate

Csales

Dcustomer_id

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping partition and order columns causes wrong grouping or ordering.

Not filtering sales before running total changes results.

Partition by region and order by date to get running totals per region over time.

5fill in blank

hard

Fill all three blanks to calculate a running total of sales per customer and region, ordered by date, including only sales in 2023.

SQL

SELECT customer_id, region, date, sales, SUM(sales) OVER (PARTITION BY [1], [2] ORDER BY [3]) AS running_total FROM sales_data WHERE EXTRACT(year FROM date) = 2023;

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

Acustomer_id

Bregion

Cdate

Dsales

Attempts:

3 left

💡 Hint

Common Mistakes

Including sales in partition or order causes errors.

Not filtering by year 2023 includes unwanted data.

Partition by customer_id and region, order by date to get running totals per customer-region over time in 2023.