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<h2>SQLite is Transactional</h2>
<p>A transactional database is one in which all changes and queries
appear to be
Atomic, Consistent, Isolated, and Durable
(<a href="http://en.wikipedia.org/wiki/ACID">ACID</a>).
SQLite implements
<a href="http://en.wikipedia.org/wiki/Serializability">serializable</a>
transactions that are atomic, consistent, isolated, and durable,
even if the transaction is interrupted by a program crash, an
operating system crash, or a power failure to the computer.
</p>
<p>
We here restate and amplify the previous sentence for emphasis:
All changes within a single transaction in SQLite either occur
completely or not at all, even if the act of writing the change
out to the disk is interrupted by
<ul>
<li>a program crash,</li>
<li>an operating system crash, or</li>
<li>a power failure.</li>
</ul>
<p>
<p>
The claim of the previous paragraph is extensively checked in the
SQLite regression test suite using a special test harness that
simulates the effects on a database file of operating system crashes
and power failures.
</p>
<p>
<a href="atomiccommit.html">Additional informaton</a>
</p>
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