Repeat Purchase Window

A medium SQL interview practice problem on DataDriven. Write and execute real sql code with instant grading.

Domain

SQL

Difficulty

medium

Seniority

L4

Problem

A churn model needs repeat-purchase signals. Find users who made another purchase within 1 to 7 days of a previous transaction, excluding same-day transactions. Return each qualifying user ID once.

Summary

The retention squad is looking for repeat purchasers.

Practice This Problem

Solve this SQL problem with real code execution. DataDriven runs your SQL queries against a real database and grades it automatically.