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Event Occurrence Counting
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Event Occurrence Counting

EasySQL · PostgreSQL

Problem

Write a query to count occurrences of specific events in a dataset.

Use the event_log table and count these event types: equipment_alarm, batch_started, and batch_completed. Exclude all other event types and NULL event types.

Output

  1. One row per requested event type, with columns event_type and event_count.
  2. Sort by event_count descending, then event_type ascending to break ties.

Schema

event_log
ColumnTypeDescription
event_idPKINTUnique event identifier
event_typeVARCHAR(50)Name of the recorded event
occurred_atTIMESTAMPTime when the event occurred
Tablesevent_log
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