Oracle流程控制语句-白红宇

1.选择语句

1.1 IF...THEN...END IF语句

DECLARE MY_AGE INT;IF MY_AGE IS NULL THEN      DBMS_OUTPUT.put_line('AGE IS NULL'); END IF;

1.2 IF...THEN ELSIF THEN....ELSE THEN... ENDIF语句，这里需要注意的是ELSIF这个，JAVA里面的写法就是 else if 这里是ELSIF，IF前面不能有空格。

IF AGE <= 6 AND AGE > 0 THEN    DBMS_OUTPUT.put_line('CHILD');  ELSIF AGE <= 17 AND AGE > 6 THEN    DBMS_OUTPUT.put_line('TEENAGER');   ELSIF AGE <= 40 AND AGE > 17 THEN    DBMS_OUTPUT.put_line('YOUTH');   ELSIF AGE <= 65 AND AGE > 40 THEN    DBMS_OUTPUT.put_line('Middle-aged');   ELSIF AGE > 65 AND AGE<= 150 THEN    DBMS_OUTPUT.put_line('OLDER');   ELSE     DBMS_OUTPUT.put_line('YOU AGE IS OUT OF SPACE');   END IF;

1.3.CASE 语句

CASE AGE    WHEN 1 THEN  DBMS_OUTPUT.put_line('BABY');    WHEN 15 THEN  DBMS_OUTPUT.put_line('TEENAGER');    WHEN 25 THEN  DBMS_OUTPUT.put_line('ADULT');    ELSE DBMS_OUTPUT.put_line('OLDER');   END CASE;   END;

2.循环语句

2.1 LOOP 语句

DECLARE RESULT NUMBER:=0;NUM1 NUMBER:=1;NUM2 NUMBER:=100; LOOP    RESULT:=RESULT+NUM1;    NUM1:=NUM1+1;    EXIT WHEN NUM1>NUM2;  END LOOP;    DBMS_OUTPUT.put_line('LOOP RESUT IS:'||RESULT);

2.2 WHILE语句

WHILE NUM1<=NUM2 LOOP    RESULT:=RESULT+NUM1;    NUM1:=NUM1+1;  END LOOP;  DBMS_OUTPUT.put_line(RESULT);

2.3 FOR语句

FOR J IN REVERSE NUM1..NUM2 LOOP    RESULT:=RESULT+J;    DBMS_OUTPUT.put_line(J);  END LOOP;  DBMS_OUTPUT.put_line(RESULT);