Smooth Latency

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

Domain

SQL

Difficulty

medium

Seniority

L5

Problem

Your team is investigating whether certain API endpoints are getting slower over time. For every row in api_calls where latency is not NULL, compute a running average of latency partitioned by endpoint and ordered by call_time, covering all calls up to and including the current one. Return endpoint, latency, and running_avg.

Summary

Noisy latency readings, smoothed into a trend you can trust.

Practice This Problem

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