DATA ls_employee_entity_key TYPE zcl_zdemo_app1_mpc=>ts_person.

    io_tech_request_context->get_converted_keys(
    IMPORTING
      es_key_values = ls_employee_entity_key
    ).

    SELECT * FROM zapp_table INTO TABLE @DATA(lt_employee) WHERE zz_number = @ls_employee_entity_key-zz_number.

    READ TABLE lt_employee  ASSIGNING FIELD-SYMBOL(<fs_empl>) INDEX 1.
    IF sy-subrc EQ 0.
      MOVE-CORRESPONDING <fs_empl> TO er_entity.
    ENDIF.