Introduction to XML
Definition:
Extensible Markup Language (XML) is a software and hardware independent tool for storing and transporting data.
That say’s it all! XML are flat files designed to carry data – with focus on what data is.
History:
XML history begins with the development of Standardized Generalized Markup Language (SGML) in the 1970’s by Charles Goldfarb along with Ed Mosher and Ray Lorie while working at IBM (Anderson, 2004).
SGML is a language used to specify mark-up languages such as Hype Text Markup Language (HTML) or XML. The purpose of SGML was to create vocabularies which could be used to mark up documents with structural tags. It was thought at the time, that certain machine readable documents should remain machine readable for perhaps decades.
HTML remains popular even today as a presentation technology and is considered unsuitable as a data storage format.
SGML was too complicated to be used to store or transport data. This gave in birth to XML.
XML bridges this gap by being both human and machine readable, while being flexible enough to support platform and architecture independent data interchange.
OpenEdge® ABL and XML – Essentials
Here are few things that I have worked in the past with OpenEdge® ABL and XML:
- Create XML using temp-table – We should be able to create an xml file out of the data in my temp-table (would use temp-table filed name as tags and attributes and the fields value as data).
- Read an XML into a temp-table – We should be able to read the data in an XML file into a temp-table (would use temp-table filed name as tags and attributes and the fields value as data).
- Create XML – We should be able to create an XML file without temp-table.
- Read an XML – We should be able to read the data in an XML file without temp-table.
While I have worked in all the four situations, my personal favorites are the first two. Nothing like working with the temp-tables.
Let’s look at each of these in this tutorial. For learning purpose, this tutorial uses sports2000 database.
Click HERE to download document tutorial on essentials of OpenEdge® ABL and XML.
Author: Raghuraman Kadambi
Linkedin: https://www.linkedin.com/pulse/openedge-abl-xml-essentials-raghuraman-kadambi-pmp/