Window Function Choice | Dataford Interview Questions

Why did you use the window function that you did, and what other window functions have you used?

Using the provided tables, demonstrate your answer by returning the most recent event for each active account, including active accounts with no events.

Output

One row per active account with account_id, account_name, event_id, event_type, and event_timestamp.
Include accounts without events, using NULL event values.
Order by account_id ascending, with the greatest event_id breaking timestamp ties.

Schema

accounts

Column	Type	Description
account_idPK	INT	Unique account identifier
account_name	VARCHAR(100)	Account display name
is_active	BOOLEAN	Whether the account is active

account_events

Column	Type	Description
event_idPK	INT	Unique event identifier
account_id	INT	Account associated with the event
event_type	VARCHAR(50)	Type of account event
event_timestamp	TIMESTAMP	Timestamp when the event occurred

Your question is Window Function Choice. 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