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Top Pages By Unique Visitors

MediumSQL · PostgreSQL00:00
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Your question is Top Pages By Unique Visitors. Start with the requirements and the two tables on the right.

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Problem

Similarweb Digital Research needs a country-level view of the most visited pages. Write a PostgreSQL query that returns the top three pages by unique visitors for every country represented in the page-view data.

Requirements

  1. Join page-view events to page metadata.
  2. Count distinct non-null visitors for each country and page.
  3. Rank pages within each country by unique visitors descending, breaking ties with the lower page_id.
  4. Return only ranks 1 through 3, ordered by country and rank.

Schema

page_views
ColumnTypeDescription
view_idPKINTEGERUnique page-view event identifier
page_idINTEGERIdentifier of the viewed page
country_codeVARCHAR(2)Two-letter visitor country code
visitor_idVARCHAR(20)Anonymized visitor identifier
pages
ColumnTypeDescription
page_idPKINTEGERUnique page identifier
page_nameVARCHAR(100)Page title from Similarweb metadata
Tablespage_viewspages
Your solutionPostgreSQL
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