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Rolling 7-Day Swipes Average

MediumSQL · PostgreSQL00:00
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Your question is Rolling 7-Day Swipes Average. Start with the requirements and the one table on the right.

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Problem

Tinder's Data Science team wants a daily engagement metric for each user. Write a PostgreSQL query that calculates the rolling 7-day average number of swipes per user from Tinder swipe activity.

Requirements

  1. Restrict activity to January 1 through January 10, 2025, including January 1 and excluding January 11.
  2. Aggregate swipe events by user and calendar day before applying the window function.
  3. Calculate the rolling 7-day average as the total swipes in the current date and preceding six calendar days divided by 7. Days without recorded swipes contribute zero.
  4. Return results ordered by user_id and swipe date.

Schema

tinder_swipes
ColumnTypeDescription
swipe_idPKINTUnique swipe event identifier
user_idINTTinder user who performed the swipe
swiped_atTIMESTAMPTimestamp when the swipe occurred
swipe_typeVARCHAR(20)Swipe classification
Tablestinder_swipes
Your solutionPostgreSQL
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