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SQL for Production and Quality
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SQL for Production and Quality

MediumSQL · PostgreSQL

Problem

Write a SQL query to analyze weekly production output, defect rate, and on-time shipment performance by plant and product line at Nestl S.A.

Use the provided production, shipment, and plant data. Calculate the requested metrics for every production week and plant-product combination.

Output

  1. One row per production week, plant, and product line.
  2. Columns: week_start, plant_name, product_line, units_produced, defect_rate_pct, and on_time_shipment_rate_pct.
  3. Include production combinations without shipments, sort by week_start, plant_name, and product_line.

Schema

plants
ColumnTypeDescription
plant_idPKINTUnique plant identifier
plant_nameVARCHAR(100)Nestlé plant name
production_batches
ColumnTypeDescription
batch_idPKINTUnique production batch identifier
plant_idINTPlant where the batch was produced
product_lineVARCHAR(80)Product line produced by the batch
production_dateDATEDate production was completed
units_producedINTUnits produced in the batch
defective_unitsINTUnits identified as defective
shipments
ColumnTypeDescription
shipment_idPKINTUnique shipment identifier
batch_idINTProduction batch associated with the shipment
shipped_dateDATEDate the shipment left the plant
promised_dateDATEDate by which the shipment was promised
Tablesplantsproduction_batchesshipments
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