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Second-Highest Consumption Query
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Second-Highest Consumption Query

MediumSQL · PostgreSQL

Problem

Write a SQL query to find the second-highest energy consumption record for a specific utility grid sector.

Use the provided sector and consumption tables. Treat the second-highest value as the second distinct non-null consumption level, returning every record tied at that level.

Output

  1. Return record_id, sector_code, consumption_kwh, and recorded_at.
  2. Include only records from sector SOUTH_BAY at the second-highest distinct consumption level.
  3. Order by consumption_kwh descending, then record_id ascending.

Schema

utility_grid_sectors
ColumnTypeDescription
sector_idPKINTUnique utility grid sector identifier
sector_codeVARCHAR(30)Business code for the grid sector
sector_nameVARCHAR(100)Human-readable sector name
energy_consumption
ColumnTypeDescription
record_idPKINTUnique energy consumption record identifier
sector_idINTReferenced utility grid sector
consumption_kwhDECIMAL(12,2)Recorded energy consumption in kilowatt-hours
recorded_atTIMESTAMPTimestamp when consumption was recorded
Tablesutility_grid_sectorsenergy_consumption
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