Oracle PLSQL 函数调用到第二个函数

Posted 2023-05-09

【中文标题】Oracle PLSQL 函数调用到第二个函数

【英文标题】：Oracle PLSQL function call into a second function

【发布时间】：2012-11-25 11:26:10

【问题描述】：

如何将第一个函数的返回值调用到第二个函数中？这是第一个计算客户访问我的商店次数的函数：

CREATE OR REPLACE  FUNCTION CALCULATE ( NUM CUSTOMER.CUST_VISIT%TYPE)
RETURN NUMBER
IS
V_CUST_VISIT NUMBER(3);
V_COUNT INTEGER;
BEGIN
SELECT CUST_VISIT
INTO V_CUST_VISIT
FROM CUSTOMER, BOOKING
WHERE CUSTOMER.CUST_ID = BOOKING.CUST_ID;
SELECT MAX(COUNT(*)) 
INTO v_count
FROM BOOKING
GROUP BY CUST_ID
HAVING count(*)>=0;

CASE v_count
WHEN 3 THEN v_cust_visit:= v_count; 
DBMS_OUTPUT.PUT_LINE('10% DISCOUNT DUE');

WHEN 6 THEN v_cust_visit:= v_count;
DBMS_OUTPUT.PUT_LINE('20% DISCOUNT DUE');

WHEN 9 THEN v_cust_visit:= v_count;
DBMS_OUTPUT.PUT_LINE('30% DISCOUNT DUE');

ELSE v_cust_visit:= v_count;
DBMS_OUTPUT.PUT_LINE('OOPS NO DISCOUNT DUE YET! AFTER THREE BOOKINGS');
END CASE;
END;
/
Where in the second function:
CREATE OR REPLACE FUNCTION CALC_BILL
(BILL_NUM TREATMENT.TREAT_COST%TYPE)

RETURN NUMBER

IS

CUST_ID VARCHAR2(4);
TREAT_COST NUMBER(10,2);
v_TREAT_cost TREATMENT.TREAT_COST%TYPE; 
DISCOUNTED_BILL NUMBER(10,2);
NO_DISCOUNT EXCEPTION;

BEGIN

SELECT TREAT_COST 
INTO v_treat_cost 

FROM CUSTOMER C, TREATMENT T, TREAT_SESSION TS
WHERE C.CUST_ID = TS.CUST_ID 
AND T.TREAT_ID = TS.TREAT_ID;

如果 CALCULATE() :=3 --这是我尝试过的方法，但没有奏效-- 然后 DISCOUNTED_BILL:= v_treat_cost-(v_treat_cost*0.1);

ELSIF 计算：= 6 然后 DISCOUNTED_BILL := v_treat_cost-(v_treat_cost*0.2);

ELSIF 计算 := 9 然后 DISCOUNTED_BILL := v_treat_cost-(v_treat_cost*0.3); 别的 提高 NO_DISCOUNT;

 END IF;
 END;
 /

【问题讨论】：

你不应该在CALCULATE 中使用CALL_BILL 吗？

【参考方案1】：

将函数调用分配给一个变量：

    some_number_result := calculate(some_input);

    if some_number_result = 1 then 
       -- do stuff
    end if;

等等……

【讨论】：

感谢 Greg，这就是我现在所做的，它看起来不错 v_CUST_VISIT := CALCULATE(DISCOUNTED_BILL); IF v_CUST_VISIT = 3 THEN DISCOUNTED_BILL:= v_treat_cost-(v_treat_cost*0.1);结束 IF;