is"><em>atomic</em></span>, so that the changes happen all at once or not at all.
They are <span class="emphasis"><em>consistent</em></span>, so that the database is in a legal state
when the transaction begins and when it ends. They are typically
<span class="emphasis"><em>isolated</em></span>, which means that any other users in the database
cannot interfere with them while they are in progress. And they are
<span class="emphasis"><em>durable</em></span>, so that if the system or application crashes after