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Rank Providers by Monthly Volume
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Rank Providers by Monthly Volume

MediumSQL · PostgreSQL

Problem

Write a query using window functions to rank healthcare providers based on their monthly booking volume within each geographic region for Zocdoc.

Use completed bookings from January and February 2025. Rows associated with a provider whose region is NULL must be ignored.

Output

  1. One row per provider, region, and month with completed bookings.
  2. Columns: region, booking_month, provider_id, provider_name, booking_volume, and regional_rank.
  3. Ties share the same rank. Sort by region, month, rank, and provider ID.

Schema

providers
ColumnTypeDescription
provider_idPKINTUnique healthcare provider identifier
provider_nameVARCHAR(100)Provider display name
regionVARCHAR(50)Geographic region for the provider
bookings
ColumnTypeDescription
booking_idPKINTUnique booking identifier
provider_idINTReferenced healthcare provider
booked_atTIMESTAMPTimestamp when the booking was created
statusVARCHAR(50)Booking lifecycle status
Tablesprovidersbookings
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Your question is Rank Providers by Monthly Volume. Start with the requirements and the two tables in the Question tab.

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