为什么 to_Char(date, 'd') 函数只是忽略了 Oracle 过程中的条件逻辑？

Question

我正在尝试查看 performanceDate 的日期，并且仅在工作日应用折扣。

//14/04/2018 星期六

v_performanceday VARCHAR(5);

SELECT PERFORMANCEDATE INTO v_performanceday FROM PERFORMANCE WHERE PERFORMANCEID = p_PerformanceID;
CASE
WHEN (to_char(v_performanceday, 'd') != '6' OR to_char(v_performanceday, 'd') != '7')
    THEN
    INSERT INTO DISCOUNT  (Reason, MembershipID, PerformanceID) 
    VALUES (p_Reason, p_MembershipID, p_PerformanceID)
    returning DiscountID into v_discountid;
    v_discountprice := 2.0;
ELSE
    RAISE_APPLICATION_ERROR(-20101, '***********Members only get discount on weekday performances!***************'); 
END CASE;

现在，我遇到了这个错误。

Error report -
ORA-06502: PL/SQL: numeric or value error: character string buffer too small
ORA-06512: at "USER2.CREATE_NEW_BOOKING", line 56
ORA-06512: at line 1
06502. 00000 -  "PL/SQL: numeric or value error%s"
*Cause:    An arithmetic, numeric, string, conversion, or constraint error
       occurred. For example, this error occurs if an attempt is made to
       assign the value NULL to a variable declared NOT NULL, or if an
       attempt is made to assign an integer larger than 99 to a variable
       declared NUMBER(2).
*Action:   Change the data, how it is manipulated, or how it is declared so
       that values do not violate constraints.

但是，如果我将第一行数据类型替换为 DATE，则无论我插入的是工作日还是周末发生的 PerformanceID，它都会应用折扣！

v_performanceday DATE;

谁能帮我弄清楚为什么它没有正确应用 to_char 函数，而当其他 case 语句按预期完美运行时却简单地忽略它？

Answer 1

v_performancedate 应该是日期 -- 这是正确的类型。

你的逻辑不正确。 or 应该是 and 。 . .或者更好，not in:

CASE WHEN to_char(v_performanceday, 'd') not in ('6', '7')

为什么 to_Char(date, 'd') 函数只是忽略了 Oracle 过程中的条件逻辑？

Why does the to_Char(date, 'd') function simply ignoring the conditional logic in Oracle procedure?

sql

oracle

oracle12c

to-char