1 <stránka

     2 	xmlns="https://trac.frantovo.cz/xml-web-generator/wiki/xmlns/strana"

     3 	xmlns:m="https://trac.frantovo.cz/xml-web-generator/wiki/xmlns/makro">

     4 	

     5 	<nadpis>Reading an Atom feed using XMLTable</nadpis>

     6 	<perex>converting arbitrary XML into relational data using XMLTable</perex>

     7 	<m:pořadí-příkladu>02800</m:pořadí-příkladu>

     8 

     9 	<text xmlns="http://www.w3.org/1999/xhtml">

    10 		

    11 		<p>

    12 			In this exaple we will achieve the same result as in <m:a href="examples-xquery-atom">previous one with XQuery</m:a>

    13 			but we will use a different tool – <code>relpipe-in-xmltable</code>.

    14 			This approach differs from XQery one in several aspects:

    15 		</p>

    16 		

    17 		<ul>

    18 			<li>no need for writing a script/program – we need just to write an one-liner resp. call one command with parameters</li>

    19 			<li>no need for an external tool like Galax, BaseX or XQilla</li>

    20 			<li>no serialization to the intermediary XML and its immediate deserialization – the XML input is parsed in the same proces which outputs relational data</li>

    21 			<li>simpler (but less powerful) tool – we write only two or more XPath expressions</li>

    22 		</ul>

    23 		

    24 		<p>This is the (shortened) structure of our XML input:</p>

    25 

    26 		<m:pre jazyk="xml" src="examples/atom-xmltable.xml"/>

    27 

    28 		<p>This pipeline will download the XML data and transform it to two relations:</p>

    29 

    30 		<m:pre jazyk="bash" src="examples/atom-xmltable.sh"/>

    31 		

    32 		<p>The first one contains individual entries and the second one contains the common header:</p>

    33 		

    34 		<m:pre jazyk="text" src="examples/atom-xmltable.txt"/>

    35 		

    36 		<p>

    37 			This example shows how to work with namespaces and how to generate multiple relations from a single XML input.

    38 			It also shows that the name of the relation do not have to be a literal but might be derived from the input document.

    39 		</p>

    40 		

    41 		<p>If we add the <code>id</code> attribute to the entries table, we can aggregate entries from various sources and still be able to JOIN them with their metadata.</p>

    42 		

    43 	</text>

    44 

    45 </stránka>