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January Campaign Metrics Quality Status
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January Campaign Metrics Quality Status

MediumSQL · PostgreSQL

Problem

How do you handle missing or inconsistent data in your reporting?

Using the provided tables, write a SQL query for January 2025 that preserves every campaign, summarizes its available metrics, and assigns a data-quality status based on missing records, null values, invalid negative values, or inconsistent campaign names.

Output

  1. One row per campaign, including campaigns with no January metrics
  2. Columns: campaign_id, campaign_name, channel, total_spend, total_conversions, and data_quality_status
  3. Order by campaign_id ascending

Output details

  • Treat January as dates >= DATE '2025-01-01' and < DATE '2025-02-01'.
  • Return totals as zero when no metrics or when the aggregate is otherwise NULL, while ignoring NULL values in sums.
  • Include negative values in totals, but classify any negative spend or conversions as INVALID_VALUES.
  • Apply status precedence: MISSING_METRICS, then MISSING_VALUES, then INVALID_VALUES, then INCONSISTENT_NAME, otherwise CLEAN.
  • Classify campaign names as inconsistent when they differ, including when exactly one compared name is NULL.

Schema

campaign_directory
ColumnTypeDescription
campaign_idPKINTUnique campaign identifier
campaign_nameVARCHAR(100)Canonical campaign name
channelVARCHAR(50)Marketing channel
is_activeBOOLEANWhether the campaign is active
campaign_daily_metrics
ColumnTypeDescription
metric_idPKINTUnique daily metric record
campaign_idINTCampaign associated with the metric
metric_dateDATEDate of the reported metric
campaign_nameVARCHAR(100)Campaign name supplied by the reporting source
spendNUMERIC(12,2)Daily campaign spend
conversionsINTDaily conversion count
Tablescampaign_directorycampaign_daily_metrics
Interviewer

Your question is January Campaign Metrics Quality Status. Start with the requirements and the two tables in the Question tab.

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