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REPORT  ztest_dynamic.
"---------------------------------------------------------------------------*
"Declaration
"---------------------------------------------------------------------------*
"Table for condition
DATA:
      wa_cond     TYPE string,
      it_cond     TYPE TABLE OF string.
"Variables
DATA:
      lv_cityfrom TYPE spfli-cityfrom.
"---------------------------------------------------------------------------*
"Selection Screen
"---------------------------------------------------------------------------*
PARAMETERS: city1(10) TYPE c, city2(10) TYPE c.

"---------------------------------------------------------------------------*
"Start of selection
"---------------------------------------------------------------------------*

START-OF-SELECTION.

  CONCATENATE 'CITYFROM = ''' city1 '''' INTO wa_cond.
  APPEND wa_cond TO it_cond.
  CLEAR  wa_cond.

  CONCATENATE 'OR CITYFROM = ''' city2 '''' INTO wa_cond.
  APPEND wa_cond TO it_cond.
  CLEAR  wa_cond.

  CONCATENATE 'OR CITYFROM = ''' 'BERLIN' '''' INTO wa_cond.
  APPEND wa_cond TO it_cond.
  CLEAR  wa_cond.
  "Check the Where wa_condition
  LOOP AT it_cond INTO wa_cond.
    WRITE wa_cond.
  ENDLOOP.
  SKIP.
  "Select Query with dynamic where clause
  SELECT  cityfrom
    INTO  lv_cityfrom
    FROM  spfli
   WHERE (it_cond).

    WRITE / lv_cityfrom.
  ENDSELECT.