SQL Query Performance Tuning | Dataford Interview Questions

Can you describe a time when you optimized a slow-running query in SQL?

You are given a query that returns active Filevine matters with their latest activity timestamp. Write a SQL query that produces the same result set efficiently.

Output

One row per matter that has at least one non-archived activity
Columns: matter_id, matter_name, latest_activity_at
Include only matters with status = 'active'
Ignore archived activities and rows where the activity timestamp is NULL
Sort by latest_activity_at descending, then matter_id ascending

Schema

matters

Column	Type	Description
matter_idPK	INT	Unique matter identifier
matter_name	VARCHAR(120)	Matter name
status	VARCHAR(20)	Matter status such as active or closed

activities

Column	Type	Description
activity_idPK	INT	Unique activity identifier
matter_id	INT	References matters.matter_id
activity_type	VARCHAR(40)	Type of activity
activity_at	TIMESTAMP	When the activity occurred
is_archived	BOOLEAN	Whether the activity is archived

Your question is SQL Query Performance Tuning. Start with the requirements and the two tables in the Question tab.

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Problem