Which of the following is the correct syntax to calculate a running total of sales using SUM as a window function in PostgreSQL?

easy📝 Syntax Q12 of 15

PostgreSQL - Window Functions in PostgreSQL

ASELECT sales, SUM(sales) OVER (ORDER BY date) AS running_total FROM sales_data;

BSELECT sales, SUM(sales) FROM sales_data ORDER BY date;

CSELECT sales, SUM(sales) PARTITION BY date FROM sales_data;

DSELECT sales, SUM(sales) OVER PARTITION BY date FROM sales_data;

Step-by-Step Solution

Solution:

Step 1: Identify correct window function syntax
SUM(sales) OVER (ORDER BY date) calculates cumulative sum ordered by date.
Step 2: Check other options for syntax errors
The other options misuse window function syntax or omit OVER keyword.
Final Answer:
SELECT sales, SUM(sales) OVER (ORDER BY date) AS running_total FROM sales_data; -> Option A
Quick Check:
SUM() OVER (ORDER BY ...) is correct syntax [OK]

Quick Trick: Use OVER() with ORDER BY for running totals [OK]

Common Mistakes:

Master "Window Functions in PostgreSQL" in PostgreSQL

9 interactive learning modes - each teaches the same concept differently

Want More Practice?

15+ quiz questions · All difficulty levels · Free