Structures

Structures are data objects that are made up of components of any data types that are stored one after the other in the memory. The data type of a structure is a structured type or a structure or database table defined in the ABAP dictionary.

In a program, a structured type or a structure is generated with the additions BEGIN OF ... END OF of statements TYPES, DATA etc. As of release 6.40, dynamic generation with methods of the RTTC is also possible.

Depending on the kinds of components, structures are designated as followed:

• Flat structures do not contain any deep components.

• Flat character-like structures are flat structures that contain only character-like components. These can be used in the same way as elementary character-like data objects. This is not the case particularly for structures that contain strings.

• Nested structures contain at least one sub-structure. Whether a nested structure is flat or character-like depends on all the components in it.

• Deep structures contain at least one deep component at any nesting level.

The following diagram illustrates a deep structure.

Note

Depending on whether a structure contains static or dynamic components, it is formally either a static or dynamic data object.