[ABAP] OData: $orderby implementieren

Variante 1

* https://blogs.sap.com/2013/09/03/sap-gw-implement-a-better-orderby-for-cust-ext-class/
* http://www.techippo.com/2016/08/sorting-query-options-orderby-sap-odata-service.html
* http://www.saplearners.com/orderby-query-option-in-sap-netweaver-gateway/
* https://blogs.sap.com/2017/12/06/display-countfilterorderbyinlinecounttop-and-skip-operations-using-odata-services/

METHOD xyz_get_entityset.

  ...

  DATA(it_orderby) = io_tech_request_context->get_orderby( ).

  IF line_exists( it_orderby[ property = 'MATNR' ] ).
    DATA(lv_orderby) = it_orderby[ property = 'MATNR' ].

    CASE lv_orderby-order.
      WHEN 'asc'.
        SORT: et_entityset BY name ASCENDING.
      WHEN 'desc'.
        SORT: et_entityset BY name DESCENDING.
    ENDCASE.
  ENDIF.

  ...

ENDMETHOD.

Variante 2

METHOD xyz_get_entityset.

  ...

  DATA(it_orderby) = io_tech_request_context->get_orderby( ).

  READ TABLE it_orderby INTO DATA(ls_orderby) INDEX 1.
  IF sy-subrc = 0.
* generische Order-Property verwenden, wenn z.B. nur ein Sortierkriterium vorhanden
* (z.B. beim Anklicken von Tabellenfeldern)
    CASE ls_orderby-order.
      WHEN 'asc'.
        SORT: et_entityset BY (ls_orderby-property) ASCENDING.
      WHEN 'desc'.
        SORT: et_entityset BY (ls_orderby-property) DESCENDING.
    ENDCASE.
  ENDIF.

  ...

ENDMETHOD.

[ABAP] Gruppierung von LOOP-Elementen (LOOP, GROUP BY), Group-Member

Beispiel 1 (einfach)

TYPES: BEGIN OF ty_person,
         person_id TYPE char3,
         name      TYPE char10,
         city      TYPE char3,
       END OF ty_person.

TYPES: ty_it_persons TYPE STANDARD TABLE OF ty_person WITH DEFAULT KEY.

DATA(it_persons) = VALUE ty_it_persons( ( person_id = 'P01' name = 'Horst' city = 'HAM' )
                                        ( person_id = 'P02' name = 'Udo'   city = 'BER' )
                                        ( person_id = 'P03' name = 'Inge'  city = 'HAM' )
                                        ( person_id = 'P04' name = 'Edit'  city = 'BER' )
                                        ( person_id = 'P05' name = 'Agnes' city = 'HAM' )
                                        ( person_id = 'P06' name = 'Ede'   city = 'LEI' ) ).

* Gruppierung nach City
* Aufsteigend sortiert
* mit Members (Unterelemente)
LOOP AT it_persons ASSIGNING FIELD-SYMBOL(<c>) GROUP BY <c>-city ASCENDING.

  LOOP AT GROUP <c> ASSIGNING FIELD-SYMBOL(<p>).
    WRITE: / '  ', <p>-person_id, <p>-name, <p>-city.
  ENDLOOP.

* neue interne Tabelle aus der Gruppe generieren
  DATA(it_cp) = VALUE ty_it_persons( FOR <cp> IN GROUP <c> ( <cp> ) ).

  ...

  ULINE.
ENDLOOP.

Beispiel 2 (WHERE, ASCENDING, ASSIGNING FIELD-SYMBOL)

TYPES: BEGIN OF ty_person,
         person_id TYPE char3,
         name      TYPE char10,
         city      TYPE char3,
         street    TYPE char20,
       END OF ty_person.

TYPES: ty_it_persons TYPE STANDARD TABLE OF ty_person WITH DEFAULT KEY.

* Testdaten mit Städten und Personen
DATA(it_persons) = VALUE ty_it_persons( ( person_id = 'P01' name = 'Horst' city = 'HAM' street = 'Allee' )
                                        ( person_id = 'P02' name = 'Udo'   city = 'BER' street = 'Kudamm' )
                                        ( person_id = 'P03' name = 'Inge'  city = 'HAM' street = 'Allee' )
                                        ( person_id = 'P04' name = 'Edit'  city = 'BER' street = 'Müllerstr.' )
                                        ( person_id = 'P05' name = 'Agnes' city = 'HAM' street = 'Hauptstraße' )
                                        ( person_id = 'P06' name = 'Ede'   city = 'LEI' street = 'Zentralplatz' )
                                        ( person_id = 'P07' name = 'Ida'   city = 'LEI' street = 'Zentralplatz' )
                                        ( person_id = 'P08' name = 'Ulf'   city = 'LEI' street = 'Poststraße' )
                                        ( person_id = 'P09' name = 'Ingo'  city = 'BER' street = 'Uferweg' )
                                        ( person_id = 'P10' name = 'Heinz' city = 'LEI' street = 'Postplatz' )
                                        ( person_id = 'P11' name = 'Heini' city = 'HAM' street = 'Postweg' )
                                      ).

* Suchkriterien für die Liste
DATA(rg_city) = VALUE rseloption( ( sign = 'I' option = 'EQ' low = 'HAM' high = '' )
                                  ( sign = 'I' option = 'EQ' low = 'LEI' high = '' ) ).

* Personenliste anhand der Suchkriterien für city durchloopen
LOOP AT it_persons ASSIGNING FIELD-SYMBOL(<g>) WHERE city IN rg_city
  GROUP BY ( city  = <g>-city       " Gruppierung nach feld 'city'
             size  = GROUP SIZE     " Anz. Elemente der akt. Gruppe in <gp>
             index = GROUP INDEX )  " Index der Gruppe <gp>
  ASCENDING AS TEXT                 " Gruppen aufsteigend sortieren
  ASSIGNING FIELD-SYMBOL(<gp>).     " Zugriff auf die Gruppe über <gp>

  WRITE: / |       City: { <gp>-city  }|.
  WRITE: / |GROUP INDEX: { <gp>-index }|.
  WRITE: / | GROUP SIZE: { <gp>-size }|.
  WRITE: / |   sy-tabix: { sy-tabix }|.

* Unterelemente der Gruppe durchloopen
  LOOP AT GROUP <gp> ASSIGNING FIELD-SYMBOL(<pi>).
    WRITE: / |     sy-tabix: { sy-tabix }|.
    WRITE: / |         data: { <pi>-city } { <pi>-person_id } { <pi>-name } { <pi>-street } |.
  ENDLOOP.

  ULINE.

ENDLOOP.

Beispiel 3 (Hierarchie)

TYPES: BEGIN OF ty_person,
         person_id TYPE char3,
         name      TYPE char10,
         city      TYPE char3,
         street    TYPE char20,
       END OF ty_person.

TYPES: ty_it_persons TYPE STANDARD TABLE OF ty_person WITH DEFAULT KEY.

* Testdaten mit Städten und Personen
DATA(it_persons) = VALUE ty_it_persons( ( person_id = 'P01' name = 'Horst' city = 'HAM' street = 'Allee' )
                                        ( person_id = 'P02' name = 'Udo'   city = 'BER' street = 'Kudamm' )
                                        ( person_id = 'P03' name = 'Inge'  city = 'HAM' street = 'Allee' )
                                        ( person_id = 'P04' name = 'Edit'  city = 'BER' street = 'Müllerstr.' )
                                        ( person_id = 'P05' name = 'Agnes' city = 'HAM' street = 'Hauptstraße' )
                                        ( person_id = 'P06' name = 'Ede'   city = 'LEI' street = 'Zentralplatz' )
                                        ( person_id = 'P07' name = 'Ida'   city = 'LEI' street = 'Zentralplatz' )
                                        ( person_id = 'P08' name = 'Ulf'   city = 'LEI' street = 'Poststraße' )
                                        ( person_id = 'P09' name = 'Ingo'  city = 'BER' street = 'Uferweg' )
                                        ( person_id = 'P10' name = 'Heinz' city = 'LEI' street = 'Postplatz' )
                                        ( person_id = 'P11' name = 'Heini' city = 'HAM' street = 'Postweg' )
                                      ).

* Gruppierung nach City
* Aufsteigend sortiert
* mit Members (Unterelemente)
LOOP AT it_persons ASSIGNING FIELD-SYMBOL(<c>) GROUP BY <c>-city ASCENDING.
* Stadt ausgeben
  WRITE: / <c>-city.

* Gruppierung nach City->Straße
* Aufsteigend sortiert
* mit Members (Unterelemente)
  LOOP AT GROUP <c> ASSIGNING FIELD-SYMBOL(<s>) GROUP BY <s>-street ASCENDING.
    WRITE: / '  ', <s>-street.

    LOOP AT GROUP <s> ASSIGNING FIELD-SYMBOL(<p>).
      WRITE: / '    ', <p>-person_id, <p>-name.
    ENDLOOP.
  ENDLOOP.

  ULINE.
ENDLOOP.

Beispiel 4 (REFERENCE INTO mit und ohne MEMBERS)

TYPES: BEGIN OF ty_person,
         person_id TYPE char3,
         name      TYPE char10,
         city      TYPE char3,
       END OF ty_person.

* Sortierte Tabelle
TYPES: ty_it_persons TYPE SORTED TABLE OF ty_person WITH UNIQUE KEY person_id.

DATA(it_persons) = VALUE ty_it_persons( ( person_id = 'P01' name = 'Horst' city = 'HAM' )
                                        ( person_id = 'P02' name = 'Udo'   city = 'BER' )
                                        ( person_id = 'P03' name = 'Inge'  city = 'HAM' )
                                        ( person_id = 'P04' name = 'Edit'  city = 'BER' )
                                        ( person_id = 'P05' name = 'Agnes' city = 'HAM' )
                                        ( person_id = 'P06' name = 'Ede'   city = 'LEI' ) ).

* Gruppierung nach City
* Aufsteigend sortiert
* WITHOUT MEMBERS -> bessere Performance, aber kein Zugriff auf Unterelemente
LOOP AT it_persons ASSIGNING FIELD-SYMBOL(<c>)
  GROUP BY ( city  = <c>-city
             size  = GROUP SIZE
             index = GROUP INDEX )
  ASCENDING
  WITHOUT MEMBERS
  REFERENCE INTO DATA(o_city).

  WRITE: / |City: { o_city->city }, Size: { o_city->size }, Index: { o_city->index }|.
ENDLOOP.

ULINE.

* Gruppierung nach City
* Aufsteigend sortiert
* mit Members (Unterelemente)
LOOP AT it_persons ASSIGNING FIELD-SYMBOL(<c2>)
  GROUP BY ( city  = <c2>-city
             size  = GROUP SIZE
             index = GROUP INDEX )
  ASCENDING
  REFERENCE INTO DATA(o_city2).

  WRITE: / |City: { o_city2->city }, Size: { o_city2->size }, Index: { o_city2->index }|.

  LOOP AT GROUP o_city2 ASSIGNING FIELD-SYMBOL(<p>).
    WRITE: / '  ', <p>-person_id, <p>-name, <p>-city.
  ENDLOOP.
ENDLOOP.

Weiterführende Infos: Link und Link