SQLSQL LabPostgreSQL practice
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J02IntermediateLEFT JOIN · COUNT

Engineer release ownership

Return every engineer as engineer_id, name, and deployment_count, including engineers with zero deployments. Sort by count descending, then name.

Data available

Use these tables

2 tables · 1 relationship
Table 1

engineers

Forward-deployed engineers who own releases.

  • engineer_idintegerPK
  • nametext
  • teamtext
Table 2

deployments

Customer releases, including failures and rollbacks.

  • deployment_idintegerPK
  • customer_idintegerFK
  • engineer_idintegerFK
  • versiontext
  • statustext
  • deployed_attimestamptz
How the tables connect
deployments.engineer_id=engineers.engineer_id
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