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Top N Per Group Query

EasySQL · PostgreSQL00:00
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Your question is Top N Per Group Query. Start with the requirements and the one table on the right.

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Problem

CustomerInsights.AI needs one highest-performing insight record from each dashboard group. Write a PostgreSQL query that returns the top record per group_name, where performance is measured by metric_value.

Requirements

  1. Return exactly one record for each group_name.
  2. Select the record with the greatest non-NULL metric_value; use the smallest record_id to break ties.
  3. Return the group, record name, and metric value, ordered by group name.

Schema

insight_records
ColumnTypeDescription
record_idPKINTUnique insight record identifier
group_nameVARCHAR(100)CustomerInsights.AI insight group
record_nameVARCHAR(150)Name of the insight record
metric_valueDECIMAL(10,2)Performance metric used for ranking
Tablesinsight_records
Your solutionPostgreSQL
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