What Is Seed Data?

Seed data is the baseline content inserted into a database to bootstrap it into a usable, known state. Test suites load seeds so queries and assertions run against predictable rows, and new environments use seeds to populate reference tables like roles or settings. Seeds are typically defined in scripts so they can be reapplied consistently.

Why it matters

A blank database makes most integration tests impossible to write deterministically. Seeding establishes the fixtures every test can rely on, so results depend on the code under test rather than leftover data.

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