SQLSQL LabPostgreSQL practice
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W05AdvancedROW_NUMBER · top N per group

Top two users per customer

Return the two most active users per customer as customer_id, user_id, event_count, and customer_rank. Break count ties by lower user_id. Sort by customer_id and rank.

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1 table
Table 1

usage_events

Product events with late and duplicate source records.

  • event_idintegerPK
  • source_event_idtext
  • user_idintegerFK
  • customer_idintegerFK
  • event_typetext
  • occurred_attimestamptz
  • ingested_attimestamptz
  • duration_msintegerNULL
  • metadatajsonb
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PostgreSQL

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