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  • PLSQL跳出嵌套循环的小例子

    开始

    DECLARE
       v_cnt NUMBER:=0;
       v_out_ext BOOLEAN:=FALSE;
       v_in_ext  BOOLEAN:=FALSE;
    BEGIN
       <<Outer_loop>>
       LOOP
             
         EXIT WHEN v_cnt>20;
    
         <<Inner_loop>>
         LOOP
             dbms_output.put_line(v_cnt);
             v_cnt:=v_cnt+1;
             
             IF v_cnt>5 THEN
                 v_in_ext:=TRUE;
             END IF;
             
             EXIT Outer_loop WHEN (v_in_ext = TRUE);         
         END LOOP; 
         dbms_output.put_line('++++++++++++++++++++');
       END LOOP;
    END;

    运行结果:

    anonymous block completed
    0
    1
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    3
    4
    5

    如果改成跳出内部循环:

    DECLARE
       v_cnt NUMBER:=0;
       v_out_ext BOOLEAN:=FALSE;
       v_in_ext  BOOLEAN:=FALSE;
    BEGIN
       <<Outer_loop>>
       LOOP
             
         EXIT WHEN v_cnt>20;
    
         <<Inner_loop>>
         LOOP
             dbms_output.put_line(v_cnt);
             v_cnt:=v_cnt+1;
             
             IF v_cnt>5 THEN
                 v_in_ext:=TRUE;
             END IF;
             
             EXIT Inner_loop WHEN (v_in_ext = TRUE);         
         END LOOP; 
         dbms_output.put_line('++++++++++++++++++++');
       END LOOP;
    END;

    运行结果:

    anonymous block completed
    0
    1
    2
    3
    4
    5
    ++++++++++++++++++++
    6
    ++++++++++++++++++++
    7
    ++++++++++++++++++++
    8
    ++++++++++++++++++++
    9
    ++++++++++++++++++++
    10
    ++++++++++++++++++++
    11
    ++++++++++++++++++++
    12
    ++++++++++++++++++++
    13
    ++++++++++++++++++++
    14
    ++++++++++++++++++++
    15
    ++++++++++++++++++++
    16
    ++++++++++++++++++++
    17
    ++++++++++++++++++++
    18
    ++++++++++++++++++++
    19
    ++++++++++++++++++++
    20
    ++++++++++++++++++++

    结束

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  • 原文地址:https://www.cnblogs.com/gaojian/p/2768455.html
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