ABAP Keyword Documentation → ABAP - Reference → Processing Internal Data
Meshes are instances of mesh types defined using
TYPES snode ... ASSOCIATION to_node
TO tnode ON tcomp1 = scomp1 [AND ...].
TYPES END OF MESH
These are special structures. Their components (referred to as nodes) are either structured internal tables or reference variables that point to structured internal tables.
ASSOCIATION enables you to define
ON conditions) between start nodes and target nodes of the mesh. These semantic relationships
between the mesh nodes can be evaluated in mesh paths. The mesh paths can be used in expressions and processing statements for meshes.
7.31 | 7.40 | 7.54
- A mesh node is addressed in the same way as a normal structure component; by using the structure component selector
-) or the object component selector (
->). The associations are evaluated in mesh paths. If no path is specified, the mesh node is handled in the same way as a normal structure component. The same applies to field symbols or reference variables that point to mesh nodes. In statement
MOVE-CORRESPONDING, a mesh is also handled like a normal structure.
- In a simple case, the relationships (implemented using associations) between mesh nodes can be compared to foreign key relationships. Here the start node of an association is the check table and the target node is the foreign key table. The use of mesh paths makes it easy for you to evaluate these relationships, without the need to program the relevant selections yourself.
The program DEMO_MESH_PACK demonstrates an application based on meshes, which analyses the repository objects in packages. All the possible uses of meshes are demonstrated and can be precisely analyzed in Debugger.