Structure of a declarative DIALOG block
A declarative DIALOG instruction is made of a single sub-dialog
block, with an optional DEFINE clause to declare local variables.
Important: Unlike procedural 
DIALOG blocks, declarative
            DIALOG blocks can only define one sub-dialog block.The dialog instruction in the declarative DIALOG block binds program variables to form fields and defines the type of interaction that will take place for the data model (simple input, list input or query). The dialog implements individual control blocks that allows you to control the behavior of the interactive instruction. The dialog can also hold action handlers.
The declarative DIALOG block can define the following dialog types:
- A list of choices controlled by a 
MENUsub-dialog block. - Simple record input with the 
INPUTsub-dialog block. - Query by example input with the 
CONSTRUCTsub-dialog block. - Read-only record list navigation with the 
DISPLAY ARRAYsub-dialog block. - Editable record list handling with the 
INPUT ARRAYsub-dialog block.