Validating Dashboard Data Accuracy | Dataford Interview Questions

Describe your process for validating data accuracy when building a dashboard for executive stakeholders.

Use the provided source and dashboard tables to demonstrate the validation process for monthly completed-transaction metrics. Return every month represented by either table and classify whether the dashboard values match the source calculations.

Output

One row per reporting month with metric_month, source revenue and count, dashboard revenue and count, revenue variance, and validation_status.
Include missing and unexpected months, and classify each row as MATCH, MISMATCH, MISSING_DASHBOARD_MONTH, or UNEXPECTED_DASHBOARD_MONTH.
Order by metric_month ascending.

Schema

source_transactions

Column	Type	Description
transaction_idPK	INT	Unique source transaction identifier
transaction_date	DATE	Date of the transaction
amount	NUMERIC(12,2)	Transaction amount
status	VARCHAR(20)	Transaction processing status

dashboard_monthly_metrics

Column	Type	Description
metric_monthPK	DATE	Month represented by the dashboard metric
reported_revenue	NUMERIC(12,2)	Revenue displayed in the dashboard
reported_transaction_count	INT	Transaction count displayed in the dashboard
refreshed_at	TIMESTAMP	Timestamp of the dashboard metric refresh

Your question is Validating Dashboard Data Accuracy. Start with the requirements and the two tables in the Question tab.

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Problem