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SQL Data Extraction
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SQL Data Extraction

MediumSQL · PostgreSQL

Problem

Write a SQL query to extract specific data from a database for Dhl Supply Chain reporting or analytics.

Using the supplied tables, report January 2025 shipment performance for every facility, including facilities with no January shipments.

Output

  1. One row per facility with facility_code, facility_name, report_month, total_shipments, delivered_shipments, on_time_deliveries, and on_time_percentage.
  2. Include delivered shipments completed by their promised date and exclude shipments outside January 2025 from the metrics.
  3. Order by facility_code ascending.

Schema

facilities
ColumnTypeDescription
facility_idPKINTUnique facility identifier
facility_codeVARCHAR(20)Operational facility code
facility_nameVARCHAR(100)Facility display name
country_codeVARCHAR(2)ISO country code
shipments
ColumnTypeDescription
shipment_idPKINTUnique shipment identifier
shipment_referenceVARCHAR(30)Shipment reference used in reporting
facility_idINTOriginating facility identifier
shipped_atTIMESTAMPShipment dispatch timestamp
promised_atTIMESTAMPPromised delivery timestamp
delivered_atTIMESTAMPActual delivery timestamp
statusVARCHAR(20)Current shipment status
Tablesfacilitiesshipments
Interviewer

Your question is SQL Data Extraction. Start with the requirements and the two tables in the Question tab.

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