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<h1>Consistency</h1>
<p>Consistency
imposes a rule that only valid data can be written to a database. When an
update is executed, the database state will change only if all the database
consistency rules are obeyed, otherwise the transaction will be rolled back and
the database restored to its consistent state. On the other hand, if all the
updates are consistent, the database will be taken to a new consistent state.</p>
<p>Consistency
rules can include: data type correctness, relation correctness, uniqueness of
data, etc.</p></div>
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This revision (1) was last Modified 2007-05-22T08:20:00 by Tetyana.
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