Dynamic SORT with multiple components

Question

Hi all,
I want to sort an internal table in this way:
SORT itab BY (component).
This is not difficult if "component" contains the name of ONE column of itab. But - and here is my problem - how can I sort with multiple components?
Like this:
SORT itab BY (comp_1) (comp_2) ... (comp_N).
The number of components (N) shall be flexible. It is not possible to concatenate the components into one string-variable. This causes an error ITAB_ILLEGAL_COMPONENT.
Brillant would be a solution which also contains the sort-direction (ASCENDING or DESCENDING for each component like this:
SORT itab BY (comp_1) (dir_1)
             (comp_2) (dir_2)
             (comp_N) (dir_N).
Is there a way to do so?
Thanks for all hints!
Mathias

Answer 1

Hi Matahias ...
From ABAP help...
SORT itab.
Extras:
1. ... BY f1 f2 ... fn
2. ... ASCENDING
3. ... DESCENDING
4. ... AS TEXT
5. ... STABLE
The syntax check performed in an ABAP Objects context is stricter than in other ABAP areas. See Field symbols not allowed as sort criterion.
Effect
The entries in the internal table are sorted in ascending order using the key from the table definition (DATA, TYPES).
Addition 1
... BY f1 f2 ... fn
Effect
Uses the sort key defined by the sub-fields f1, f2, ..., fn of the table itab instead of the table key. The fields can be of any type; even number fields and tables are allowed.
You can also specify the sort fields dynamically in the form (name). If name is blank at run time, the sort field is ignored. If itab is a table with a header line, you can also use a field symbol pointing to the header line of itab as a dynamic sort criterion. A field symbol that is not assigned is ignored. If a field symbol is assigned, but does not point to the header line of the internal table, a runtime error occurs.
If the line type of the internal table contains object reference variables as components, or the entire line type is a reference variable, you can use the attributes of the object to which a reference is pointing in a line as sort criteria (see Attributes of Objects as the Key of an Internal Table
You can address the entire line of an internal table as the key using the pseudocomponent TABLE_LINE. This is particularly relevant for tables with a non-structured line type when you want to address the whole line as the key of the table (see also Pseudocomponent TABLE_LINE With Internal Tables).
If you use one of the additions 2 to 5 before BY, it applies to all fields of the sort key by default. You can also specify these additions after each individual sort field f1, f2, ..., fn. For each key field, this defines an individual sort rule which overrides the default.
Cheers
Preetham