When you bind the fields in a form design to a data source, you create an association between the form design and the data source that allows you to capture, present, move, process, output, and print information associated with the form design.
If some fields on a form are bound to a data source, data in fields that are not bound will be lost when the form is saved in Acrobat. If you want to bind some fields to a data source, all fields for which you want to save the data must be bound.
LiveCycle Designer ES enables you to use client-side or server-side binding. Using client-side binding, you can make immediate changes to the data. Server-side binding requires that you submit back to the server to commit changes to the data.
To perform client-side binding, you must have Acrobat or Adobe Reader (with a rights-enabled form) installed. You need LiveCycle Forms ES on a Microsoft server to do server-side database binding.
You can drag a node or a node and its descendants from the Data View palette onto the page and automatically create a bound field or multiple fields or subforms. The form field or subform, and its descendants, are bound to the data source. In addition, form field properties are automatically set according to the properties of the data binding. For example, the form object’s type, name, and caption all reflect those of the binding object.
You can drag a node from the Data View palette onto an existing field on the page and bind the two. You also have the option of updating the form field’s properties to match those of the binding object. The properties that can be updated depend on the combination of form object type and binding type. For information about the properties that can be updated, see Binding Properties dialog box.
Select an object on the page and then select the node to which you want to bind the object in the Binding tab of the Object palette. The form field’s properties can be updated in the same way as if you dragged a node from the Data View palette onto an existing form field. For information about the properties that can be updated, see Binding Properties dialog box.
Letting LiveCycle Designer ES auto-generate bound fields into a subform
You can generate new bound fields in a subform from the Data View palette.
See also 

About binding fields to a data source