SQLSQL LabPostgreSQL practice
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O06Advanceddata quality · COUNT DISTINCT

Duplicate ingestion impact

For each customer with duplicate source events, return customer_id, raw_event_count, unique_source_events, and duplicate_rows (raw minus unique). Sort duplicate_rows descending, then customer_id.

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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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