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SQL for Top Energy Regions

MediumSQL · PostgreSQL00:00
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Your question is SQL for Top Energy Regions. Start with the requirements and the three tables on the right.

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Problem

Write a SQL query to find the top three energy-consuming regions per month from a transactional dataset.

Use the supplied region, meter, and transaction data. Include only posted transactions with non-null, non-negative consumption and a recorded timestamp. Ties at the third rank should be included.

Output

  1. One row per qualifying region and month, with month_start, region_name, total_kwh, and energy_rank.
  2. Sort by month_start, energy_rank, then region_name.

Schema

regions
ColumnTypeDescription
region_idPKINTUnique region identifier
region_nameVARCHAR(100)Region name
meters
ColumnTypeDescription
meter_idPKINTUnique meter identifier
region_idINTRegion containing the meter
meter_statusVARCHAR(30)Operational status of the meter
energy_transactions
ColumnTypeDescription
transaction_idPKINTUnique transaction identifier
meter_idINTMeter reporting the consumption
recorded_atTIMESTAMPTimestamp when consumption was recorded
consumed_kwhDECIMAL(12,2)Energy consumption in kilowatt-hours
statusVARCHAR(30)Transaction processing status
Tablesregionsmetersenergy_transactions
Your solutionPostgreSQL
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