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SQL Case With Data Results
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SQL Case With Data Results

MediumSQL · PostgreSQL

Problem

Describe a case where you used SQL to analyze marketing data and produced results with data.

Using the supplied marketing tables, write a query that summarizes performance for every campaign. Include campaigns without recorded activity and treat missing numeric activity as zero where appropriate.

Output

  1. One row per campaign with campaign_id, campaign_name, channel, total_impressions, total_clicks, total_conversions, total_spend, ctr_pct, and conversion_rate_pct
  2. Include all campaigns, including those without metric rows; rates are NULL when their denominator is zero
  3. Order by total_conversions descending, then campaign_id ascending

Schema

campaigns
ColumnTypeDescription
campaign_idPKINTUnique campaign identifier
campaign_nameVARCHAR(120)Campaign display name
channelVARCHAR(40)Marketing channel
statusVARCHAR(20)Campaign status
campaign_daily_metrics
ColumnTypeDescription
metric_idPKINTUnique daily metric record identifier
campaign_idINTReferenced campaign identifier
metric_dateDATEDate of recorded activity
impressionsINTNumber of impressions
clicksINTNumber of clicks
conversionsINTNumber of conversions
spendNUMERIC(12,2)Marketing spend
Tablescampaignscampaign_daily_metrics
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