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Monthly Interaction Trends by Segment
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Monthly Interaction Trends by Segment

MediumSQL · PostgreSQL

Problem

Write a PostgreSQL query to identify monthly customer interaction trends across Mölnlycke channels. For each month and customer segment, return total interactions, resolved interactions, resolution rate, and the most-used channel. Only keep month-segment groups with at least 2 interactions.

Schema

Tables
  • customers(customer_id, customer_name, segment, region)
  • interaction_channels(channel_id, channel_name)
  • customer_interactions(interaction_id, customer_id, channel_id, interaction_date, interaction_type, status, satisfaction_score)

What This Tests

  • Joining fact and dimension tables
  • Monthly aggregation with date formatting
  • Conditional aggregation using CASE WHEN
  • Using CTEs to isolate channel ranking logic
Tablescustomersinteraction_channelscustomer_interactions
Interviewer

Your question is Monthly Interaction Trends by Segment. Start with the requirements and the three tables in the Question tab.

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