Starting the PV-WAVE XML Toolkit
At the WAVE> prompt, enter the following commands to load and initialize the PV-WAVE XML Toolkit:
@Xml_Startup
or
Xml_Init
PV‑WAVE XML Toolkit Capabilities
Data Interchange Is Convenient
XML is quickly becoming a standard for interchanging structured information among different hardware, software, and operating systems. PV‑WAVE can be integrated into any application where XML is used as a common communication protocol. If you can access your XML data from the computer on which PV‑WAVE is running, you can extract, analyze, sort, and customize this data within PV‑WAVE.
Use the Standard XML XPATH Syntax
You can query or update your XML data from PV‑WAVE using the XML path language (XPATH) commands. You do not need to learn new syntax or complicated function and procedure calls.
For XML queries, PV‑WAVE XML Toolkit retrieves all of the nodes specified by the XPATH statement. The results of the query are placed in a PV‑WAVE table variable.
The Simple API for XML (SAX) is Supported
If your XML data is too large to process with simple XPATH statement, you can use the Simple API for XML (SAX) to perform the same task. This is an “event-driven” API. For example, the start of an element in an XML document generates an event and notifies the user-defined function with the information associated with this event. One application of this feature is that you can retrieve the data incrementally without having to maintain a copy of the entire XML document in memory. For more information, refer to the SaxInit Procedure of the PV‑WAVE Reference manual.
Handling Data Inside PV-WAVE
PV‑WAVE XML Toolkit imports query data into a PV‑WAVE table variable. This format is very convenient for using other PV‑WAVE procedures and functions to analyze and display the data from the query. Almost all PV‑WAVE functions can access the data directly from the table. In addition, PV‑WAVE has some procedures and functions that are specially designed to work with table variables. For more information, refer to the PV‑WAVE functions BUILD_TABLE, QUERY_TABLE, UNIQUE, GROUP_BY, and ORDER_BY.
In addition to reading from an XML source, you can also create new or modify previously parsed XML DOM (Document Object Model) trees in memory and from this generate XML documents to be saved in files or passed to other applications.
