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SQL Failure Modes by Region
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SQL Failure Modes by Region

MediumSQL · PostgreSQL

Problem

Given a dataset of equipment failure logs, write a SQL query to find the top 3 most frequent failure modes per region.

Use equipment_failure_logs as the source table. Exclude records with a missing region or failure mode. If failure modes have equal frequencies, order them alphabetically and include at most three modes per region.

Output

  1. One row per selected region and failure mode.
  2. Columns: region, failure_mode, failure_count, and failure_rank.
  3. Sort by region alphabetically, then failure_rank ascending.

Schema

equipment_failure_logs
ColumnTypeDescription
log_idPKINTUnique failure log identifier
regionVARCHAR(50)Operational region where the failure occurred
failure_modeVARCHAR(100)Observed equipment failure mode
failure_dateDATEDate the failure was recorded
Tablesequipment_failure_logs
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