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Top Channels by Engagement
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Top Channels by Engagement

MediumSQL · PostgreSQL

Problem

Write a SQL query using window functions to identify the top three media channels by user engagement for each healthcare campaign at Omnicom Health.

Use the provided campaign and engagement event data. Treat total engagement as the sum of valid engagement scores, excluding events without a campaign, channel, or user.

Output

  1. One row per qualifying campaign and media channel, with campaign_name, channel_name, total_engagement, and engagement_rank.
  2. Include at most the three highest-ranked channels per campaign.
  3. Order by campaign name, engagement rank, and channel name. Break ties alphabetically by channel name.

Schema

campaigns
ColumnTypeDescription
campaign_idPKINTUnique healthcare campaign identifier
campaign_nameVARCHAR(150)Healthcare campaign name
engagement_events
ColumnTypeDescription
event_idPKINTUnique engagement event identifier
campaign_idINTReferenced healthcare campaign
channel_nameVARCHAR(100)Media channel associated with the event
user_idVARCHAR(40)User associated with the engagement event
engagement_scoreINTEngagement value contributed by the event
Tablescampaignsengagement_events
Interviewer

Your question is Top Channels by Engagement. Start with the requirements and the two tables in the Question tab.

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