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Running Total With Window Functions
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Running Total With Window Functions

EasySQL · PostgreSQL

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

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

Schema

user_orders
ColumnTypeDescription
order_idPKINTUnique identifier for each order
user_idINTIdentifier of the user who placed the order
order_dateDATEDate when the order was created
order_amountDECIMAL(10,2)Order value, may be NULL for incomplete records
channelVARCHAR(20)Order source channel
Tablesuser_orders
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