基本語法

程式碼

DECLARE V_STRING VARCHAR2(20); V_DIAMETER NUMBER(5, 2); V_CIRCUMFERENCE NUMBER(5, 2); V_RADIUS NUMBER(5, 2) := 5; C_PI CONSTANT NUMBER(3,2) := 3.14; V_COUNTER NUMBER(5); BEGIN -- THIS IS SINGLE-LINE COMMENT /* THIS IS MULTI-LINE COMMENT */ V_DIAMETER := 9; V_CIRCUMFERENCE := V_DIAMETER * C_PI; DBMS_OUTPUT.PUT_LINE('V_CIRCUMFERENCE = ' || V_CIRCUMFERENCE); IF V_RADIUS IS NULL THEN DBMS_OUTPUT.PUT_LINE('V_RADIUS IS NULL.'); ELSIF V_RADIUS > 9 THEN DBMS_OUTPUT.PUT_LINE('V_RADIUS IS GREATER THAN 9.'); ELSIF V_RADIUS < 9 THEN DBMS_OUTPUT.PUT_LINE('V_RADIUS IS LESS THAN 9.'); ELSE DBMS_OUTPUT.PUT_LINE('V_RADIUS IS EQUAL TO 9.'); END IF; V_COUNTER := 1; LOOP EXIT WHEN V_COUNTER >= 6; DBMS_OUTPUT.PUT_LINE('LOOP: V_COUNTER = ' || V_COUNTER); V_COUNTER := V_COUNTER + 1; END LOOP; V_COUNTER := 1; WHILE (V_COUNTER <= 5) LOOP DBMS_OUTPUT.PUT_LINE('WHILE LOOP: V_COUNTER = ' || V_COUNTER); V_COUNTER := V_COUNTER + 1; EXIT WHEN V_COUNTER >= 9; END LOOP; FOR V_LOCAL_COUNTER IN 1 .. 5 LOOP DBMS_OUTPUT.PUT_LINE('FOR LOOP: V_LOCAL_COUNTER = ' || V_LOCAL_COUNTER); END LOOP; FOR V_LOCAL_COUNTER IN REVERSE 1 .. 5 LOOP DBMS_OUTPUT.PUT_LINE('FOR LOOP REVERSE: V_LOCAL_COUNTER = ' || V_LOCAL_COUNTER); END LOOP; END; /

 

執行結果

V_CIRCUMFERENCE = 28.26 V_RADIUS IS LESS THAN 9. LOOP: V_COUNTER = 1 LOOP: V_COUNTER = 2 LOOP: V_COUNTER = 3 LOOP: V_COUNTER = 4 LOOP: V_COUNTER = 5 WHILE LOOP: V_COUNTER = 1 WHILE LOOP: V_COUNTER = 2 WHILE LOOP: V_COUNTER = 3 WHILE LOOP: V_COUNTER = 4 WHILE LOOP: V_COUNTER = 5 FOR LOOP: V_LOCAL_COUNTER = 1 FOR LOOP: V_LOCAL_COUNTER = 2 FOR LOOP: V_LOCAL_COUNTER = 3 FOR LOOP: V_LOCAL_COUNTER = 4 FOR LOOP: V_LOCAL_COUNTER = 5 FOR LOOP REVERSE: V_LOCAL_COUNTER = 5 FOR LOOP REVERSE: V_LOCAL_COUNTER = 4 FOR LOOP REVERSE: V_LOCAL_COUNTER = 3 FOR LOOP REVERSE: V_LOCAL_COUNTER = 2 FOR LOOP REVERSE: V_LOCAL_COUNTER = 1