I simply got an internet site assignment also it server apparently doesn't support databases. So I believed, inside a traditional XML DTD...we've data such as this:

<book category="CHILDREN">
    <title>Harry Potter</title>
    <author>J K. Rowling</author>
    <year>2005</year>
    <price>29.99</price>
</book>

Using Text Boxes and perhaps by connecting using XSLT or something like that else, can one add/place more data into my existing XML sheet??

Also, can one perform validation for example no duplicate game titles??

I am type of a new comer to this plus some help could be appreciated.

If this sounds like about adding "rows" for your book "record", then this can be done

<xsl:template match="/">
  <xsl:apply-templates/>
</xsl:template>

<!-- match book explicitly ... -->
<xsl:template match="book">
  <xsl:copy>
    <xsl:apply-templates select="@*|node()"/>

    <!-- and add one "row" to the books content -->
    <one-more-row>value</one-more-row>
  </xsl:copy>
</xsl:template>

<!-- Just copy all the other elements/attributes (including book contents) -->
<xsl:template match="@*|node()">
  <xsl:copy>
    <xsl:apply-templates select="@*|node()"/>
  </xsl:copy>
</xsl:template>