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SQL for Top Converting Channels
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SQL for Top Converting Channels

MediumSQL · PostgreSQL

Problem

Write a query to identify the top 3 performing marketing channels by conversion rate at Veeva Systems.

Use the marketing_channels and marketing_leads tables. Treat leads with status = 'converted' as conversions and exclude channels with no leads.

Output

  1. Return one row per selected channel with channel_name, total_leads, conversions, and conversion_rate.
  2. Calculate conversion_rate as converted leads divided by total leads, expressed as a percentage rounded to two decimal places.
  3. Sort by conversion rate descending, then total leads descending, then channel name ascending. Return only three rows.

Schema

marketing_channels
ColumnTypeDescription
channel_idPKINTUnique identifier for a marketing channel
channel_nameVARCHAR(100)Name of the marketing channel
marketing_leads
ColumnTypeDescription
lead_idPKINTUnique identifier for a marketing lead
channel_idINTMarketing channel that generated the lead
statusVARCHAR(30)Current lifecycle status of the lead
Tablesmarketing_channelsmarketing_leads
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