Rank Transactions with Window Functions | Dataford Interview Questions

Write a query using window functions to rank customer transactions by date within each account.

Use the provided account and transaction data. Include only transactions associated with a known account, and assign the same rank to transactions sharing a date.

Output

One row per included transaction with account_id, customer_id, transaction_id, transaction_date, and transaction_rank.
Order by account, transaction date ascending with null dates last, then transaction ID.
Rank independently within each account.

Schema

accounts

Column	Type	Description
account_idPK	INT	Unique account identifier
customer_id	INT	Customer associated with the account
account_type	VARCHAR(30)	Type of financial account
account_status	VARCHAR(20)	Current account status

transactions

Column	Type	Description
transaction_idPK	INT	Unique transaction identifier
account_id	INT	Account associated with the transaction
transaction_date	DATE	Date the transaction was posted
amount	DECIMAL(12,2)	Transaction amount
transaction_type	VARCHAR(30)	Transaction classification

Your question is Rank Transactions with Window Functions. Start with the requirements and the two tables 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