Professional BizTalk® Server 2006

5.1. The Orchestration Execution Environment

This section covers the environment that underpins BizTalk orchestration and details the many features that are required to enable business processes to be expressed and executed within BizTalk.

We'll start with covering how BizTalk orchestrations are implemented under the covers and detail how they are activated and versioned. We'll also cover persistence points, which you must understand to create BizTalk orchestrations that perform and scale well.

After covering these fundamentals, we'll cover orchestration development in more detail.

5.1.1. Implementation

In this section, we'll detail how BizTalk orchestrations are actually implemented under the covers. Although this is completely transparent to a solution developer, it's often important to understand how things work under the covers to enable effective debugging.

Although not essential, it is useful to understand how orchestrations are compiled and subsequently executed at runtime. When designing your BizTalk orchestration using the Orchestration Designer, each orchestration will have an associated ODX file. This file represents the shapes in the orchestration and their associated configuration, including any code that has been written in expression shapes. The collection of these defines the orchestration.

The ODX file contains both XML and a language that, on first sight, looks like C# but is in fact a private BizTalk language called X#. Interestingly, both the XML and X# represent ...