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

Domain

SQL

Difficulty

medium

Seniority

L5

Problem

Given a table of customer transactions, identify users who made at least two purchases within a 7-day window. Return each qualifying user ID once.

Summary

They bought again within seven days.

Practice This Problem

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