xml2 vs XMLFunctions

<div class="Section1"><p class="MsoNormal"><span lang="DE">Hi,</span><p class="MsoNormal"><span lang="DE"> </span><p
class="MsoNormal">Iam writing you this mail, because I am currently using xml2 functionality in PostgreSQL 8.3.x and
wantto substitute it by the newer API as mentioned here:<p class="MsoNormal"> <p class="MsoNormal">>From <span
class="productname">PostgreSQL</span>8.3 on, there is XML-related functionality based on the SQL/XML standard in the
coreserver. That functionality covers XML syntax checking and XPath queries, which is<p class="MsoNormal">>what this
moduledoes, and more, but the API is not at all compatible. It is planned that this module will be removed in
PostgreSQL8.4 in favor of the newer standard API, so you are <p class="MsoNormal">>encouraged to try converting your
applications.If you find that some of the functionality of this module is not available in an adequate form with the
newerAPI, please explain your <p class="MsoNormal">>issue to pgsql-hackers@postgresql.org so that the deficiency can
beaddressed.<p class="MsoNormal"> <p class="MsoNormal">The only function of xml2 I ever used was
“xpath_bool(document,query)returns bool” where document represents a table column. How can I do this with the new API
?<pclass="MsoNormal">I thought that <a name="FUNCTIONS-XML-PROCESSING">“9.14.2. Processing XML</a>: xpath(xpath, xml[,
nsarray])”might be the right function, but I don’t know how to specify the column where the xml is stored.<p
class="MsoNormal">Canyou please give me an example ? I only have to implement xpath functions that return Boolean. I’d
liketo query – SELECT foo FROM bar AS x WHERE xpath(‘xpath’, x.xmlcolumn [,nsarray])<p class="MsoNormal"> <p
class="MsoNormal"> <pclass="MsoNormal">Cheers, Tobias<p class="MsoNormal"> <p class="MsoNormal"> </div>