Day-one login retention

What this task practices

Day-one login retention is a sql case interview exercise that trains prompt interpretation, explicit assumptions, a concrete response, and a clear explanation of tradeoffs. The catalog marks it as medium difficulty. It focuses on Data Reasoning, Performance Analysis, Technical Reasoning. The signed-in workspace provides the tools for the round and evaluates the attempt against task-specific criteria. Reference solutions, hidden checks, evaluator instructions, and candidate work remain private.