Handling Large Datasets | Dataford Interview Questions

How do you handle large datasets?

Using a single PostgreSQL table, write a query that produces a compact summary of processed records. Return the three categories with the most processed records, along with their record counts and total amounts.

Output

One row per category, limited to the top three categories
Columns: category, record_count, and total_amount
Sort by record_count descending, then category ascending to break ties

Schema

records

Column	Type	Description
record_idPK	INT	Unique record identifier
category	VARCHAR(100)	Category assigned to the record
status	VARCHAR(30)	Processing status of the record
amount	DECIMAL(12,2)	Amount associated with the record

Your question is Handling Large Datasets. Start with the requirements and the one table 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

How do you handle large datasets?

Output

One row per category, limited to the top three categories
Columns: category, record_count, and total_amount
Sort by record_count descending, then category ascending to break ties

Schema

records

Column	Type	Description
record_idPK	INT	Unique record identifier
category	VARCHAR(100)	Category assigned to the record
status	VARCHAR(30)	Processing status of the record
amount	DECIMAL(12,2)	Amount associated with the record

Your question is Handling Large Datasets. Start with the requirements and the one table 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.