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SQL for Underperforming Work Centers
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SQL for Underperforming Work Centers

MediumSQL · PostgreSQL

Problem

Given a table of operational output, how would you write a query to identify the top three underperforming work centers over a specific period?

Use January 2025 as the period. Underperformance is measured as total target units minus total actual units, and NULL actual values should count as zero.

Output

  1. Return one row per underperforming work center with work_center_id, work_center_name, total_target, total_output, and shortfall_units.
  2. Include only work centers with a positive shortfall, ordered by shortfall_units descending, with work_center_id ascending as the tie-breaker.
  3. Return only the top three rows.

Schema

operational_output
ColumnTypeDescription
output_idPKINTUnique operational output record identifier
work_center_idINTIdentifier of the work center
work_center_nameVARCHAR(100)Name of the work center
work_dateDATEDate of the operational output
target_unitsINTUnits targeted for the work center on the date
actual_unitsINTUnits actually produced on the date
Tablesoperational_output
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