BizTalk Server: Basics principles of Maps – What are maps and where BizTalk can use them? (Part 2)

Posted: March 30, 2012 in BizTalk
Tags: , , , ,

BizTalk maps are graphical representations of XSLT (Extensible Stylesheet Language Transformation) documents that allow us to perform, in a simple and visual manner, transformations between XML messages.

We can enumerate the following standards used in the BizTalk Mapper:

  • XML (Extensible Markup Language) – designed to transport and store data of messages;
  • XML Schema (XSD – XML Schema Definition) – describes the structure of an XML document;
  • E XSLT (Extensible Stylesheet Language Transformation) – is a style sheet language for XML documents (stands for XSL Transformations), it defines the transformation rules of the messages;

To emphasize, that they all are W3C recommendation. W3C ((Worldwide Web Consortium)) is an international consortium where Member organizations, a full-time staff, and the public work together to develop Web standards.

We can define that there are two types of transformations:

  • Syntax Transformations: This type of transformations occurs in the receive or send pipelines and aim to transform a document into another representation, e.g. CSV to XML. Here the document maintains the same data (semantics), but changes the syntax that is represented. I.e. we translate the document, but typically we don’t modify the structure. Normally, this type of transformation is bidirectional, since we still have the same semantic content, we can apply the same transformation logic and obtain the document in its original format.

Syntax-Transformations

  • Semantic Transformations: This type of transformation usually occurs only in BizTalk maps. Here the document maintains the same syntax that is represented (XML), but changes its semantics (data content). This type of transformation are typically one-way, since that when we added and aggregate small parts of the information, that compose the document into another differently document, we may miss important details for its reconstruction.

Semantic-Transformations

Note: In this article we will talk only of semantic transformations, i.e., maps in BizTalk.

Where maps can be used?

Maps can be used for processing messages received at a receive port, inside orchestrations or for processing messages sent to a send port, as the following figure suggest:

Where-maps-can-be-used

The biggest difference between using maps in ports or in orchestrations is that, when we use maps inside orchestrations we can have multiple messages inputs (transformations of many documents into one final document – transformations N -> 1) and ports only allows a single input message (transformations 1 -> 1).

Related links

Comments
  1. K K Aggarwal says:

    Can i use a map inside another map or use a part of map multiple times in the same map. Just like we can do with functions ?

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s