Query

Exchanger XML Editor currently supports the XQuery language, as implemented in release 8.4 of Saxon (see http://saxon.sourceforge.net).

Execute XQuery

The XQuery project contains a sample input file projects/XQuery/input/books.xml containing a list of books with their titles and authors and also a sample query file projects/XQuery/query/books.xq. The query in this case sorts the books in order of the length of their titles. Select Transform->Execute XQuery and enter the appropriate input and query files.The output of the transformation can be sent to a new window or saved to file. Notice that in the resultant document, the books have now been sorted with the shortest title first.

Database Access

The latest Saxon XSL processor provides extensions that allow data to be retrieved from database tables. Database drivers must be added manually by adding the jars in the System tab of File->Preferences - this requires a restart of the application to take affect.

The built-in sample is for the MySQL database and performs a simple SQL Select-From-Where query. To test the database access, install the appropriate jar, edit the existing Scenario by selecting Transform->Manage Scenario, choose "Simple Database Access" and press the Change button. Click on the Parameters... button in the XSLT section of the dialog to see the current settings. The default driver details are for MySQL so, if necessary, modify this parameter to match the driver for your database. Now change the mandatory database name, user, password and table parameters to suit your setup. Other optional parameters include "column" which is a comma separated list of the columns that should be returned by the query - by default all (*) will be returned. Also a "where" condition can be specified to narrow the search criteria.

Save the changes you have made to the Scenario and then execute it using Transform->Execute Scenario. If the connection is successful, the query will return data in a new window - otherwise, check the Output tab for information on possible error conditions.

Note that the XSLT 2.0 version of the Saxon processor must be used to avail of this functionality (see the Processor... section of the Scenario dialog). More information on using the Saxon sql extensions can be found in the sql-extension.html file in the doc directory.