ABAP游标详解编程语言

DATA: BEGIN OF count_line,  
        carrid TYPE spfli-carrid,  
        count  TYPE i,  
      END OF count_line,  
      spfli_tab TYPE TABLE OF spfli.  
 
DATA: dbcur1 TYPE cursor,  
      dbcur2 TYPE cursor.  
 
OPEN CURSOR @dbcur1 FOR  
  SELECT carrid, count(*) AS count  
         FROM spfli  
         GROUP BY carrid  
         ORDER BY carrid.  
 
OPEN CURSOR @dbcur2 FOR  
  SELECT *  
         FROM spfli  
         ORDER BY carrid.  
 
DO.  
  FETCH NEXT CURSOR @dbcur1 INTO @count_line.  
  IF sy-subrc <> 0.  
    EXIT.  
  ENDIF.  
  FETCH NEXT CURSOR @dbcur2  
    INTO TABLE @spfli_tab PACKAGE SIZE @count_line-count.  
ENDDO.  
 
CLOSE CURSOR: @dbcur1,  
              @dbcur2. 

DATA: wa_spfli   TYPE spfli, 
      wa_sflight TYPE sflight, 
      wa_sflight_back TYPE sflight. 
 
DATA: c1 TYPE cursor, 
      c2 TYPE cursor. 
 
OPEN CURSOR @c1 FOR 
  SELECT * 
    FROM spfli 
    ORDER BY PRIMARY KEY. 
 
OPEN CURSOR @c2 FOR 
  SELECT * 
         FROM sflight 
         ORDER BY PRIMARY KEY. 
 
DATA(out) = cl_demo_output=>new( ). 
 
DO. 
  FETCH NEXT CURSOR @c1 INTO @wa_spfli. 
  IF sy-subrc NE 0. 
    EXIT. 
  ENDIF. 
  out->begin_section( 
    |{ wa_spfli-carrid } { wa_spfli-connid }| ). 
  DO. 
    IF NOT wa_sflight_back IS INITIAL. 
      wa_sflight = wa_sflight_back. 
      CLEAR wa_sflight_back. 
    ELSE. 
      FETCH NEXT CURSOR @c2 INTO @wa_sflight. 
      IF  sy-subrc <> 0. 
        EXIT. 
      ELSEIF wa_sflight-carrid <> wa_spfli-carrid 
          OR wa_sflight-connid <> wa_spfli-connid. 
        wa_sflight_back = wa_sflight. 
        EXIT. 
      ENDIF. 
    ENDIF. 
    out->write( 
     |{ wa_sflight-carrid } { 
        wa_sflight-connid } { 
        wa_sflight-fldate }| ). 
  ENDDO. 
  out->end_section( ). 
ENDDO. 
 
CLOSE CURSOR: @c1, @c2. 
 
out->display( ).