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Query Top Product Lines
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Query Top Product Lines

MediumSQL · PostgreSQL

Problem

Write a query to find the top three performing product lines based on monthly output.

Use the provided production records and identify the three highest-output product lines for each calendar month. Rank ties alphabetically by product line name.

Output

  1. One row per selected product line and month.
  2. Columns: output_month, product_line_name, monthly_output, and monthly_rank.
  3. Return exactly three rows per month when at least three product lines have records, ordered by month, rank, and product line name.

Schema

product_lines
ColumnTypeDescription
product_line_idPKINTUnique product line identifier
product_line_nameVARCHAR(100)Display name of the product line
manager_nameVARCHAR(100)Assigned product line manager
production_output
ColumnTypeDescription
output_idPKINTUnique production output record identifier
product_line_idINTProduct line associated with the output
output_dateDATEDate on which output was recorded
output_quantityINTQuantity produced in the record
Tablesproduct_linesproduction_output
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