Measure Week-Over-Week Metric Changes | Dataford Interview Questions

You are given weekly operational performance data for a delivery marketplace. Write a PostgreSQL query that compares each week's metric to the prior week for the same metric and returns the absolute change and percentage change. Use a window function such as LAG or LEAD to measure the shift over time.

Schema

weekly_ops_metrics

Column	Type	Description
metric_date	DATE	Week-ending date for the metric snapshot
metric_name	VARCHAR(100)	Name of the operational metric
metric_value	NUMERIC(12,2)	Measured value for that week

Your question is Measure Week-Over-Week Metric Changes. Start with the requirements and the one table in the Question tab.

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

Problem

Schema

weekly_ops_metrics

Column	Type	Description
metric_date	DATE	Week-ending date for the metric snapshot
metric_name	VARCHAR(100)	Name of the operational metric
metric_value	NUMERIC(12,2)	Measured value for that week

Your question is Measure Week-Over-Week Metric Changes. Start with the requirements and the one table in the Question tab.

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