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Handling Large Datasets
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Handling Large Datasets

MediumSQL · PostgreSQL

Problem

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

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

Schema

records
ColumnTypeDescription
record_idPKINTUnique record identifier
categoryVARCHAR(100)Category assigned to the record
statusVARCHAR(30)Processing status of the record
amountDECIMAL(12,2)Amount associated with the record
Tablesrecords
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