WHILE 循环中的 PL/SQL 增量答案

【问题标题】：PL/SQL increment in a WHILE loopWHILE 循环中的 PL/SQL 增量
【发布时间】：2016-04-22 09:43:56
【问题描述】：

我正在尝试计算用给定金额可以购买的物品总数。为此，我尝试创建一个带有 WHILE 循环的块，以增加项目的成本，直到满足美元价值（100 美元），但无法弄清楚如何正确计算循环。

DECLARE
lv_totavail_num NUMBER(8,2) := 100;
lv_itemprice_num NUMBER(8,2);
lv_totamt_num NUMBER(8,2);
lv_loopnum_num NUMBER(8,2) := 0;
BEGIN
DBMS_OUTPUT.PUT_LINE('Total Starting Amount: ' || lv_totavail_num);
SELECT price
INTO lv_itemprice_num
FROM BB_PRODUCT
WHERE IDPRODUCT = 4;
DBMS_OUTPUT.PUT_LINE('Price: ' || lv_itemprice_num);
WHILE lv_totavail_num >= lv_itemprice_num LOOP
lv_totavail_num := lv_itemprice_num * lv_loopnum_num;
lv_loopnum_num := lv_loopnum_num + 1;
END LOOP;
DBMS_OUTPUT.PUT_LINE('Number of Items Purchased that can be purchased: ' || lv_loopnum_num);
DBMS_OUTPUT.PUT_LINE('Total Amount: '|| lv_loopnum_num * lv_itemprice_num);
END;

【问题讨论】：

标签： plsql while-loop increment

【解决方案1】：

您的 while 内容不正确。使用lv_totamt_num 计算价格。还有其他一些小事。检查以下内容：

DECLARE
lv_totavail_num NUMBER(8,2) := 100;
lv_itemprice_num NUMBER(8,2) := 0;
lv_totamt_num NUMBER(8,2) := 0;
lv_loopnum_num NUMBER(8,2) := 0;
BEGIN
DBMS_OUTPUT.PUT_LINE('Total Starting Amount: ' || lv_totavail_num);

SELECT price
INTO lv_itemprice_num
FROM BB_PRODUCT
WHERE IDPRODUCT = 4;
DBMS_OUTPUT.PUT_LINE('Price: ' || lv_itemprice_num);
WHILE lv_totavail_num >= lv_totamt_num LOOP
lv_loopnum_num := lv_loopnum_num + 1;
lv_totamt_num := lv_itemprice_num * lv_loopnum_num;

END LOOP;
lv_loopnum_num := lv_loopnum_num -1;
DBMS_OUTPUT.PUT_LINE('Number of Items Purchased that can be purchased: ' ||lv_loopnum_num  );
DBMS_OUTPUT.PUT_LINE('Total Amount: '|| lv_loopnum_num * lv_itemprice_num);
END;

【讨论】：

谢谢