Design a unique referral code system
Source: interviewintermediate
WHAT IT TESTS: uniqueness under concurrency and code-space sizing. OUTLINE: a unique DB constraint as the source of truth, generation via random retry or an encoded counter, and collision handling.
WHAT IT TESTS: whether you can guarantee uniqueness under concurrency and reason about a small code space. ANSWER OUTLINE: enforce uniqueness with a database unique constraint that is the real arbiter, generate codes either by random sampling with retry on the constraint violation or by encoding a monotonic counter into a base-N alphabet, and validate by an indexed lookup.
Read the original → interview
- #referral-system
- #database-design
- #uniqueness
- #concurrency
- #schema
Get five bites like this every day.
Tezvyn delivers a daily feed of 60-second tech bites with quizzes to lock in what you learn.