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SQL Inner Join

EasySQL · PostgreSQL00:00
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Your question is SQL Inner Join. Start with the requirements and the one table on the right.

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Problem

Wolfspeed's manufacturing systems track production lots for silicon carbide wafer processing. Write a PostgreSQL query that returns only released lots from the Epi process area.

Requirements

  1. Return the lot number, process area, lot status, and wafer count.
  2. Include only rows where process_area is Epi and lot_status is Released.
  3. Sort the results by lot_number in ascending order.

Schema

production_lots
ColumnTypeDescription
lot_idPKINTEGERUnique production lot identifier
lot_numberVARCHAR(20)Manufacturing lot number
process_areaVARCHAR(30)Manufacturing process area
lot_statusVARCHAR(20)Current lot status
wafer_countINTEGERNumber of wafers in the lot
Tablesproduction_lots
Your solutionPostgreSQL
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