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Top Watch Time Percentile
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Top Watch Time Percentile

MediumSQL · PostgreSQL

Problem

Write a query to identify the top 10% of users based on watch time over the last 30 days.

Use the users and watch_sessions tables. Include users with no qualifying watch activity, and use user_id ascending as the deterministic tie-breaker.

Output

  1. One row per selected user.
  2. Columns: user_id, display_name, total_watch_seconds, and watch_rank.
  3. Include only the highest-ranked 10% of users, ordered by watch_rank, then user_id.

Schema

users
ColumnTypeDescription
user_idPKINTUnique user identifier
display_nameVARCHAR(100)User display name
account_statusVARCHAR(20)Current account status
watch_sessions
ColumnTypeDescription
session_idPKINTUnique viewing session identifier
user_idINTUser who watched the content
started_atTIMESTAMPSession start timestamp
watch_secondsINTNumber of seconds watched
device_typeVARCHAR(30)Device used for viewing
Tablesuserswatch_sessions
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Your question is Top Watch Time Percentile. Start with the requirements and the two tables in the Question tab.

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CodePostgreSQL
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