Help needed on workin with LDBs using call through Function Module LDB_PROC

Question

Hi All
I am new to Logical Databases. I found on net that I can use a dynamic call to a Logical Database using Function Module
"LDB_PROCESS".
I tried implementing the same using the following logic.
REPORT  zsa_test2.
TABLES: pernr.
SELECT-OPTIONS s_pernr FOR pernr-pernr.
DATA: callback TYPE TABLE OF ldbcb,
           callback_wa LIKE LINE OF callback.
callback_wa-ldbnode     = 'PERNR'.
callback_wa-get            = 'X'.
callback_wa-cb_prog     = sy-repid.
callback_wa-cb_form     = 'CALLBACK_PERNR'.
APPEND callback_wa TO callback.
START-OF-SELECTION.
  CALL FUNCTION 'LDB_PROCESS'
       EXPORTING
            ldbname                       = 'PNP'
         VARIANT                       = ' '
         EXPRESSIONS              = TEXPR
         FIELD_SELECTION        = FSEL
       TABLES
            callback                         = callback
         SELECTIONS                 = SELTAB
    EXCEPTIONS
         LDB_NOT_REENTRANT      = 1
         LDB_INCORRECT               = 2
         LDB_ALREADY_RUNNING  = 3
         LDB_ERROR                      = 4
         LDB_SELECTIONS_ERROR = 5
         LDB_SELECTIONS_NOT_ACCEPTED = 6
         VARIANT_NOT_EXISTENT      = 7
         VARIANT_OBSOLETE            = 8
         VARIANT_ERROR                  = 9
         FREE_SELECTIONS_ERROR = 10
         CALLBACK_NO_EVENT         = 11
         CALLBACK_NODE_DUPLICATE     = 12
         OTHERS                                       = 13.
  IF sy-subrc <> 0.
   WRITE: 'Exception with SY-SUBRC', sy-subrc.
  ENDIF.
*&      Form  CALLBACK_SPFLI
      text
     -->NAME       text
     -->WA         text
     -->EVT        text
     -->CHECK      text
FORM callback_pernr USING name  TYPE ldbn-ldbnode
                                            wa    TYPE pernr
                                            evt   TYPE c
                                            check TYPE c.
  BREAK-POINT.
  WRITE: / wa-pernr.
  ULINE.
ENDFORM.                    "CALLBACK_SPFLI
But I am unable to transfer the control to the subroutine. The break-point isn't reached.
Can someone please guide me? Am I using the wrong node or something??

Answer 1

look at the below code ..
pass  sstab  to the selection in the FM
data cbtab type table of ldbcb.
data wa_cbtab like line of cbtab.
data sstab type table of rsparams.
data wa_sstab like line of sstab.
wa_cbtab-ldbnode  = 'SPFLI'.
wa_cbtab-get      = 'X'.
wa_cbtab-get_late = ' '.
wa_cbtab-cb_prog  = sy-cprog.
wa_cbtab-cb_form  = 'CB_SPFLI'.
append wa_cbtab to cbtab.
wa_cbtab-ldbnode  = 'SFLIGHT'.
wa_cbtab-get      = 'X'.
wa_cbtab-get_late = ' '.
wa_cbtab-cb_prog  = sy-cprog.
wa_cbtab-cb_form  = 'CB_SFLIGHT'.
append wa_cbtab to cbtab.
wa_sstab-selname  = 'AIRP_FR'.
wa_sstab-kind     = 'S'.
wa_sstab-sign     = 'I'.
wa_sstab-option   = 'EQ'.
wa_sstab-low      = 'FRA'.
append wa_sstab to sstab.
call function 'LDB_PROCESS'
  exporting
    ldbname     = 'F1S'
  tables
    callback    = cbtab
    selections  = sstab .
form cb_spfli  using  nodename  type ldbn-ldbnode
                      wa_spfli  type spfli
                      mode      type c
                      selected  type c.
   write: / wa_spfli-carrid,
            wa_spfli-connid,
            wa_spfli-airpfrom,
            wa_spfli-airpto.
endform.
form cb_sflight  using  nodename   type ldbn-ldbnode
                        wa_sflight type sflight
                        mode       type c
                        selected   type c.
   write: /3 wa_sflight-fldate,
             wa_sflight-seatsmax,
             wa_sflight-seatsocc.
endform.