SQL Grouping and Ordering | Dataford Interview Questions

Write a SQL query to find the total volume or count of transactions by terminal, grouped by day, and ordered by the busiest days.

Use the transaction and terminal data provided. Return one row for each terminal and transaction date, excluding transactions that do not match a known terminal.

Output

Columns: terminal_code, terminal_name, transaction_day, transaction_count, and total_volume
One row per terminal per day
Order by transaction count descending, then transaction date ascending and terminal code ascending for ties

Schema

transactions

Column	Type	Description
transaction_idPK	INT	Unique transaction identifier
terminal_code	VARCHAR(20)	Code identifying the transaction terminal
transaction_ts	TIMESTAMP	Timestamp when the transaction occurred
volume	NUMERIC(12,2)	Transaction volume

terminals

Column	Type	Description
terminal_codePK	VARCHAR(20)	Unique terminal code
terminal_name	VARCHAR(100)	Terminal display name
region	VARCHAR(50)	Operational region containing the terminal

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