Zorba (XQuery Processor)

Zorba is an open source query processor written in C++, implementing
* several W3C XQuery and XML specifications and
* the JSONiq language for processing JSON data.

Zorba is distributed under Apache License, Version 2.0.
The project is mainly supported by th
FLWOR Foundation
Oracle, an
28msec

Specifications

Zorba provides the implementation of the following W3C specifications:

XQuery 1.0

XQuery 3.0


XQuery Update Facility 1.0

XQuery and XPath Full Text 1.0

XML Syntax for XQuery 1.0

XML Schema

XSL Transformations (XSLT)

XSL Formatting Objects

Zorba also provides implementations of:
* JSONiq
* Scripting Extension
* Data Definition Facility

Scripting

Scripting Extension
is an open specification that provides semantic for side-effects in XQuery or JSONiq programs.
It also provides a user-friendly syntax for imperative programming within such programs.
The following code snippet is an example of the Scripting syntax. It computes a sequence containing all the Fibonacci numbers that are less than 100.

(: this is a variable declaration statement :)
variable $a as xs:integer := 0;
variable $b as xs:integer := 1;
variable $c as xs:integer := $a + $b;
variable $fibseq as xs:integer* := ($a, $b);

while ($c lt 100) {
(: this is a variable assignment statement :)
$fibseq := ($fibseq, $c);
$a := $b;
$b := $c;
$c := $a + $b;
}
$fibseq

The following is an example of CRUD operations using Scripting, XQuery, and XQuery Update.

variable $stores := doc("stores.xml")/stores;


(: Create :)
insert node 4NY into $stores;

(: Update :)
replace value of node $stores/store tate="NY"store-number with "5";

(: Delete :)
delete node $stores/store tate != "NY"

(: Read :)
$stores

Data Definition Facility

Data Definition Facility
provides a semantic for persistent artifacts such as collections and indexes in XQuery or JSONiq programs.
For instance, the following code snippets declares a collection named ''entries'' and an index on that collection named ''entry''.

module namespace g = "http://www.zorba-xquery.com/guestbook";

import module namespace db = "http://www.zorba-xquery.com/modules/store/static/collections/dml";

declare namespace an = "http://www.zorba-xquery.com/annotations";

(: Declares a collection named entries :)
declare collection g:entries as element(entry);
(: Declares a variable that points to the g:entries collection :)
declare variable $g:entries := xs:QName('g:entries');

(: Declares an index named entry on top of the entries collection :)
declare %an:automatic %value-equality index g:entry
on nodes db:collection(xs:QName('g:entries'))
by xs:string(@id) as xs:string;

Storage

Zorba provides a pluggable store so it can be used on different kind of environments: disk, database, browser.
By default, Zorba is built with a main memory store
28msec
implements a store on top of MongoDB.
Th
XQuery in the Browser
project has built a browser plugin for Zorba and leverages the DOM as its store.

APIs

Zorba is usable throug
different host languages
C++, C, XQJ / Java, PHP, Python, C#, Ruby, and eve
XQuery/JSONiq

Zorba is also available as
command-line tool

XQDT
is an XQuery plugin for the Eclipse (IDE). It fully supports Zorba API and syntax.

Modules

Zorba provides more than 70 XQuery modules for building applications. Some of these modules are:
* File system, Email, HTTP client, OAuth client
* XQuery and JSONiq Data Model Processing: typing, atomic items, and nodes.
* Full-text: tokenizer, stemmer, thesaurus lookup.
* Data Cleaning: phonetic similarities, set similarities, conversions.
* Data Conversion: Base64, CSV, HTML, JSON, XML
* Data Formatting: XSL-FO
* Introspection and Reflection
* Cryptography
* Image processing

External links

Zorba website

Zorba live demo

Zorba modules

XQuery processors
XML