Running Total With Window Functions

EasySQL · PostgreSQL00:00

Practice interviewer

In session

5 left

00:00

Your question is Running Total With Window Functions. Start with the requirements and the one table on the right.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

You need to log in / sign up to run or submit.

Problem

Sparksoft wants to show each user's cumulative spend over time in its analytics view. Write a SQL query to calculate a running total of order amounts for every user, ordered by purchase date.

Requirements

Return one row per order.
Show user_id, order_date, order_amount, and the cumulative spend as running_total.
Reset the running total for each user.
Order the final result by user_id, then order_date, then order_id.

Schema

user_orders

Column	Type	Description
order_idPK	INT	Unique identifier for each order
user_id	INT	Identifier of the user who placed the order
order_date	DATE	Date when the order was created
order_amount	DECIMAL(10,2)	Order value, may be NULL for incomplete records
channel	VARCHAR(20)	Order source channel

Tablesuser_orders

Your solutionPostgreSQL

You need to log in / sign up to run or submit.

Run a query to see results