intermediateTesting the Persistence Layer — @DataJpaTest & Testcontainers

What does Testcontainers actually do differently from an embedded database like H2?

It spins up a real, ephemeral Docker container running the actual production database engine (real PostgreSQL, for instance) for the duration of the test run, rather than an in-memory approximation — tests run against genuinely the same engine as production, catching database-specific behavior an embedded database can't.

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