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Top Providers by Monthly Sessions
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Top Providers by Monthly Sessions

MediumSQL · PostgreSQL

Problem

Write a SQL query using window functions to identify the top three most active providers based on monthly session volumes.

Use the providers and sessions tables. Count sessions for known providers by calendar month, and use provider_id as the deterministic tie-breaker.

Output

  1. One row per provider-month in the top three for that month
  2. Columns: session_month, provider_id, provider_name, session_volume, and monthly_rank
  3. Sort by month ascending, then rank ascending

Schema

providers
ColumnTypeDescription
provider_idPKINTUnique provider identifier
provider_nameVARCHAR(100)Provider display name
sessions
ColumnTypeDescription
session_idPKINTUnique session identifier
provider_idINTProvider associated with the session
session_startedTIMESTAMPTimestamp when the session started
Tablesproviderssessions
Interviewer

Your question is Top Providers by Monthly Sessions. Start with the requirements and the two tables in the Question tab.

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