SQLite WAL improves concurrency. It doesn’t create more writers.

Write-ahead logging lets readers continue while a writer appends changes to a separate log. A checkpoint later transfers those changes into the database. This is a strong fit for many small applications, but SQLite still permits only one writer at a time. Long-running readers can also delay checkpoint progress and let the WAL grow.

SQLite

Why it matters

Useful when choosing storage for persistent jobs, local applications, and services running on a single server.

More context

Treat checkpointing and transaction length as part of operations. A WAL database has associated files; use SQLite-aware backup procedures rather than copying only the main file while writes continue. The official guide explains the concurrency and filesystem requirements.

Keep in mind

WAL requires cooperating processes on the same host and does not make SQLite a distributed database.

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