Oracle中EXIT Statement用于终止循环语句的关键字-5. 示例代码

参考官方文档地址
https://docs.oracle.com/en/database/oracle/oracle-database/23/lnpls/EXIT-statement.html#GUID-66E20B6C-3606-42AD-A7DB-C8EC782B94D8

5.1. WHILE LOOP 使用EXIT语句终止WHILE循环

在这个示例中，当变量a的值大于15时，使用EXIT语句终止WHILE循环。

DECLARE  
    a NUMBER(2) := 10;  
BEGIN  
    WHILE a < 20 LOOP  
        DBMS_OUTPUT.PUT_LINE('value of a: ' || a);  
        a := a + 1;  
        IF a > 15 THEN  
            EXIT; -- 终止循环  
        END IF;  
    END LOOP;  
END;  
/

5.2. 带EXIT语句的基本LOOP语句

在这个示例中，基本LOOP语句中的EXIT语句无条件地将控制转移到当前循环的末尾。
In this example, the EXIT statement inside the basic LOOP statement transfers control unconditionally to the end of the current loop.

DECLARE
  x NUMBER := 0;
BEGIN
  LOOP
    DBMS_OUTPUT.PUT_LINE ('Inside loop:  x = ' || TO_CHAR(x));
    x := x + 1;
    IF x > 3 THEN
      EXIT;
    END IF;
  END LOOP;
  -- After EXIT, control resumes here
  DBMS_OUTPUT.PUT_LINE(' After loop:  x = ' || TO_CHAR(x));
END;
/
 

5.3. 带有EXIT WHEN语句的基本LOOP语句

在这个示例中，当x大于3时，基本LOOP语句中的EXIT WHEN语句将控制权转移到当前循环的末尾。
In this example, the EXIT WHEN statement inside the basic LOOP statement transfers control to the end of the current loop when x is greater than 3.

DECLARE
  x NUMBER := 0;
BEGIN
  LOOP
    DBMS_OUTPUT.PUT_LINE('Inside loop:  x = ' || TO_CHAR(x));
    x := x + 1;  -- prevents infinite loop
    EXIT WHEN x > 3;
  END LOOP;
  -- After EXIT statement, control resumes here
  DBMS_OUTPUT.PUT_LINE('After loop:  x = ' || TO_CHAR(x));
END;
/