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Top Equipment Failures with Window Functions
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Top Equipment Failures with Window Functions

MediumSQL · PostgreSQL

Problem

Given a table of production logs, how would you identify the top three equipment failures using a window function?

Use the production_logs table and consider only rows representing failures with a non-null failure code.

Output

  1. One row per failure code ranked among the most frequent failures.
  2. Columns: failure_code, failure_count, and failure_rank.
  3. Include ranks 1 through 3, order by failure_rank ascending, then failure_code ascending, and include ties at the third rank.

Schema

production_logs
ColumnTypeDescription
log_idPKINTUnique production log identifier
equipment_idVARCHAR(30)Equipment that generated the log
failure_codeVARCHAR(40)Categorized equipment failure code
event_typeVARCHAR(20)Type of production event
logged_atTIMESTAMPTime when the event was recorded
failure_duration_minutesINTDuration of the failure in minutes
Tablesproduction_logs
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