Binding Definition in Workflow

In general programming style, assignment statements are used to assign one variable's value to other variable or it may happen that after performing some set of operations, finally the result might be assigned to a variable.  In the same way even the exchange of data can be performed in the workflows too. In general programming approach all the variables declaration is done at the beginning of the programming. In workflow, variables (called as ELEMENTS) are declared in a CONTAINER. Container is a place where the required elements are declared.

SAP Definition for Container: 

A basic common data structure of the various definition components and execution components of SAP Business Workflow. 

There are 5 different containers

• Workflow container
• Task container
• Method container
• Rule container
• Event container

Elements required in the workflow are declared in the workflow container, Elements required in the task are declared in the task container, so on for remaining containers too. During execution of the workflow it happens all the time that values are exchanged between two different containers. In workflow, exchanging of data between two different containers is possible by BINDING.

What is binding?

In workflow terms, the word binding represents, assignment between elements of two different containers. Binding editor is used to define binding between elements of different containers. Binding editor looks like below screen shot. For more information

Points to be noted while defining binding between elements of different containers, 

• Elements should belong to same data type.
• Binding can be defined between compatible data types. 

For more Information

Possible Binding Definitions between Containers:  

Workflow Container:

• Binding can be defined from Workflow to Event Container.
• Binding can be defined from Workflow to Task Container.
• Binding can be defined from Workflow to Rule Container.  

Event Container:

• Binding can be defined from Event container to Workflow Container.
• Binding can be defined from Event container to Task container.

Task Container:  

• Binding can be defined from Task to Workflow container.
• Binding can be defined from Task to Rule container.
• Binding can be defined from Task to Method container.  

Method Container: 

• Binding can be defined from Method to Task container and method container.

Rule Container:

• Binding can be defined from Rule container to Workflow container. 
  

Possible Binding Matrix:

Yes:  Represents that only you can export a Business object which should belong to type AAGENT.
Yes:  This binding definition is only possible for the step EVENT CREATOR.

Possible Binding Picture

The above image is reference took from SAP help documentation, to build the Possible Binding Matrix. For more information on Binding defintion

Thank You