<chapter>
    <title>Data Model</title>
    <section>
        <title>Syntax For Data Model</title>
    </section>
    <section>
        <title>XML</title>
        <section>
            <title>Basic Syntax</title>
        </section>
        <section>
            <title>XML and Semistructured Data</title>
        </section>
    </section>
</chapter>
