18.1.4- The Data Revolution

The Data Revolution

As computers have found their way into more areas of our work and home life, we are storing ever-increasing amounts of information electronically. The tendency is to think of our business data mainly residing in relational databases, such as SQL Server, Oracle or DB2. The reality, however, is that we probably have more data in other formats:

• Quotes and reports in word processor formats, such as Word or Word Perfect
• Web pages in HTML
• Presentations in PowerPoint
• Mail and memos in mail servers such as Exchange and Notes

Some of this data is replicated and some of it is as good as lost, because not everyone knows how to access it. In addition, the ubiquity of the Internet has meant that we are trying to share more and more data with people in other physical places.

But what has all this got to do with XML? Going back to our book example, Wrox uses the type of book information we have just seen for many purposes: for web pages, trade catalogs, public catalogs, information for retail purchasers (bookshops) and so on. Many of these require the information in different formats so we need to be able to use the information in different ways.

The great news is that if we can mark up our book details just once in XML, and then we can re-purpose it. So, if we were to create an XML file containing all of our book catalog we would not need to put it in HTML for the web, and then individually mail the retailers with new book details, and so on. As we will see later in the chapter, we can just re-format the one XML source to suit each purpose.

Furthermore, if people want to find out about specific books, they could just collect information about those that they are interested in, rather than wasting bandwidth having to download a large file with a lot of irrelevant data. This is because we can easily offer a search facility that goes through <title> elements looking for the title they want.