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<chapter id="datatype">

<title id="datatype-title">Data Types</title>

<para>

The data type <type>xml</type> can be used to store XML data. Its

advantage over storing XML data in, say, atext field is that it

advantage over storing XML data in a <type>text</type> field is that it

checks the input values for well-formedness, and there are support

functions to perform type-safe operations on it; see <xref

linkend="functions-xml">. Currently, there is no support for

validation against a specific <acronym>XML</> schema.

</para>

<para>

<acronym>XML</> (Extensible Markup Language) support is not one

capability, but a varietyoffeatures supported by a database

validation, indexing, efficiency of modification, searching,

<acronym>XML</> (Extensible Markup Language) support is not

just the existanceofan <type>xml</type> data type, but a

capabilities include import/export, indexing, searching,

transforming, and <acronym>XML</> to <acronym>SQL</> mapping.

<productname>PostgreSQL</> supports some but not all of these

<acronym>XML</> capabilities. Future releases of

<productname>PostgreSQL</> will continue to improve <acronym>XML</>

support. For an overview of <acronym>XML</> use in databases, see <ulink

<acronym>XML</> capabilities. For an overview of <acronym>XML</>

use in databases, see <ulink

url="http://www.rpbourret.com/xml/XMLAndDatabases.htm"></>.

</para>