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Top N Per Category with Windows
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Top N Per Category with Windows

MediumSQL · PostgreSQL

Problem

Write a SQL query to identify the top N records per category using window functions.

For this exercise, set N to 2. Use the supplied tables and return only records belonging to a known category.

Output

  1. One row per selected record, with category_name, record_id, record_name, score, and category_rank.
  2. Include the two highest-scoring records in each category. Break score ties by lower record_id.
  3. Sort by category_name, then category_rank, then record_id.

Schema

categories
ColumnTypeDescription
category_idPKINTUnique category identifier
category_nameVARCHAR(100)Category display name
records
ColumnTypeDescription
record_idPKINTUnique record identifier
category_idINTReferenced category identifier
record_nameVARCHAR(100)Record display name
scoreNUMERIC(10,2)Score used for ranking records
Tablesrecordscategories
Interviewer

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CodePostgreSQL
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