The Shape of a Run

A medium Data Modeling interview practice problem on DataDriven. Write and execute real data modeling code with instant grading.

Domain

Data Modeling

Difficulty

medium

Seniority

L5

Problem

Every machine in our fleet emits one log line when a process starts and a separate line when it stops, and each line records the machine, a process id the machine assigns locally, which kind of event it was, and a timestamp in float seconds. The warehouse has to keep every line exactly as it arrived so analysts can reconcile a start with its matching stop themselves, computing the average elapsed time per process, drawing per-machine timelines of every process in order, and flagging starts that never got a stop. Design the data model behind this log and describe how the daily files load in through an ETL.

Summary

Two log lines bracket every process. Pair them and the fleet's rhythm appears.

Practice This Problem

Solve this Data Modeling problem with real code execution. DataDriven runs your solution and grades it automatically.