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SQL Sort Query

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

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Problem

Thales Ground Master radar systems record signal readings from monitored tracks. Write a PostgreSQL query that returns the readings sorted by signal strength from the lowest value to the highest value.

Requirements

  1. Return sensor_id, radar_name, and signal_strength from radar_readings.
  2. Sort signal_strength in ascending order, place NULL values after known readings, and use sensor_id as a tie-breaker.

Schema

radar_readings
ColumnTypeDescription
sensor_idPKINTUnique identifier for the radar reading
radar_nameVARCHAR(100)Name of the Ground Master radar station
signal_strengthNUMERIC(6,2)Recorded signal strength, which may be unknown
recorded_atTIMESTAMPTimestamp when the reading was captured
Tablesradar_readings
Your solutionPostgreSQL
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