Tuesday, December 05, 2006

XQueryP: An XML Application Development Language


XQueryP: An XML Application Development Language

Presenter: Daniela Florescu, Senior Consultant, Oracle Corporation

XML 2006 Tues. 10:30

XQuery semantics were carefully specified to side-effect free

AND and OR are distributable
order of evaluation is irrelevant

New additions to XQuery for updates: insert, delete, rename, etc.

These are not fully-composable with the rest of the language.

XQueryP Overview

  • - A small language extension
  • - Supported by Oracle, BEA, DataDirect, etc.
  • - Proposed to W3C
  • - Details:

  • * A well-defined evaluation order for XQuery expressions ("sequential order") [this is a big change!!!]
  • * adds new expressions: block, set, while, break, continue
  • * error handling (try/catch)
  • * added a way to model graphs in XML
  • * a way of mapping XQueryp <-> Web services (optional)

New Expression Types:

Block Expressions

{ block-decl;... expr;... }

Assignment expressions

set $varName := exprSingle

Functions and blocks
declare updating function local:prune($d as xs:integer) as xs:integer {
declare $count as xs:inteer := 0;
for $m in /mail/message[date lt $d]
return { do delete $m;
set $count :- $count + 1
while ( condition ) {


Post a Comment

<< Home