0

在这里，我尝试根据使用程序订购的数量给予折扣。但我不知道如何将列的值分配给过程中的变量。

这是我的代码：

create column table "KABIL_PRACTICE"."SALES_IF_ELSE"
(
"SALES_ID" integer,
"PRODUCT_ID" integer,
"QTY" integer,
"DISCOUNT" integer,
"SALES_AMOUNT" Double
);

insert into "KABIL_PRACTICE"."SALES_IF_ELSE" ("SALES_ID","PRODUCT_ID","QTY","SALES_AMOUNT") values (1,101,15,1500);
insert into "KABIL_PRACTICE"."SALES_IF_ELSE" ("SALES_ID","PRODUCT_ID","QTY","SALES_AMOUNT") values (2,102,25,2500);
insert into "KABIL_PRACTICE"."SALES_IF_ELSE" ("SALES_ID","PRODUCT_ID","QTY","SALES_AMOUNT") values (3,103,35,3500);
insert into "KABIL_PRACTICE"."SALES_IF_ELSE" ("SALES_ID","PRODUCT_ID","QTY","SALES_AMOUNT") values (4,104,40,4000);
insert into "KABIL_PRACTICE"."SALES_IF_ELSE" ("SALES_ID","PRODUCT_ID","QTY","SALES_AMOUNT") values (5,105,27,2700);
insert into "KABIL_PRACTICE"."SALES_IF_ELSE" ("SALES_ID","PRODUCT_ID","QTY","SALES_AMOUNT") values (6,106,32,3200);
insert into "KABIL_PRACTICE"."SALES_IF_ELSE" ("SALES_ID","PRODUCT_ID","QTY","SALES_AMOUNT") values (7,107,19,1900);

create procedure "KABIL_PRACTICE"."IF_ELSE_DISC"
language sqlscript
as begin
declare QTY integer ;
select "QTY" from "KABIL_PRACTICE"."SALES_IF_ELSE" := QTY;
if ( QTY > 25)
then
update "KABIL_PRACTICE"."SALES_IF_ELSE" set "DISCOUNT" = 5;
else if
update "KABIL_PRACTICE"."SALES_IF_ELSE" set "DISCOUNT" = 1;
end if;
end if;
end;

任何人帮助我....

4

2 回答 2

2

这是一个没有充分使用 SQL 而是试图在 SQL 数据库上强制使用命令式编程风格的经典案例。您要做的就是根据条件更新表，不是吗？

在这种情况下，根本不需要过程逻辑（对于任何 SQL 数据库都是如此）。

UPDATE "KABIL_PRACTICE"."SALES_IF_ELSE" 
SET "DISCOUNT" = (CASE WHEN "QTY" >25 
                     THEN 2 
                     ELSE 1 
                  END) ;

这将"DISCOUNT"在单个命令中将计算值存储在表中，无需循环。

于 2017-08-23T23:27:29.013 回答
1

您可以通过在变量中选择列来分配变量。例如：

SELECT QTY INTO QTY FROM KABIL_PRACTICE.SALES_IF_ELSE
于 2017-08-28T08:14:18.403 回答