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SQL Fundamentals
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SQL Fundamentals

MediumSQL · PostgreSQL

Problem

Are you good at SQL?

Given the services and monitoring_events tables, write a query for January 2025 that summarizes events for every active service, including services with no matching events.

Output

  1. One row per active service with service_name, event_count, critical_count, and avg_resolution_minutes.
  2. Sort by event_count descending, then service_name ascending.

Schema

services
ColumnTypeDescription
service_idPKINTUnique service identifier
service_nameVARCHAR(100)Service display name
is_activeBOOLEANWhether the service is currently active
monitoring_events
ColumnTypeDescription
event_idPKINTUnique monitoring event identifier
service_idINTReferenced service identifier
occurred_atTIMESTAMPTimestamp when the event occurred
severityVARCHAR(20)Event severity
resolution_minutesDECIMAL(8,1)Minutes required to resolve the event
Tablesservicesmonitoring_events
Interviewer

Your question is SQL Fundamentals. Start with the requirements and the two tables in the Question tab.

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