Question

我有两个输入表 input_table_1如下所示：

prod_id store id    net_sales   gender  color
1   1   34  m   blue
2   1   43  f   green
3   2   12  f   green
4   3   22  f   blue
5   3   56  m   black
6   3   4   f   green

第二个表是look_up_table，它具有表1的列名及其值：

attribut  value_1
gender  m
gender  f
color   blue
color   green
color   black
.           .
.           .
.           .

我已创建此代码，其中我运行嵌套循环并在temp变量中存储attribute和value_1的值。现在我想从input_table_1中选择net_sales的总和，其中列名存储在temp_atr_val中，单元格值为temp_val。我正在尝试这样的东西，但它不适合我，temp_sales变量不会取任何值。请帮助我如何使用select语句选择属性的特定值的销售总和。

代码：

declare 
temp_atr_val varchar2(400);
temp_val varchar2 (400);
temp_name varchar2 (400);
temp_sum_percent decimal (10,3);
temp_variable number := 786;
column_count number ; 
val_count number;
temp_storeid number (38,0);
temp_sales number ; 
store_count number;
/*  sales_store number; */
BEGIN   
create table store_table as 
select distinct id_dmstore 
from input_table_1
order by store_id;   

select count(distinct attribute) into column_count from look_up_table;
for ind in 1..column_count loop

    /* putting current value of attribute from look_up_table in temp variable*/
    select attribute into temp_atr_val from (
        select attribute, rownum rwn
        from 
        (
           select distinct attribute
           from look_up_table
           order by attribute
        )
    ) where rwn = ind;

    select count( value ) into val_count from look_up_table
   where ATTRIBUTE = temp_atr_val;

    for ind in 1..val_count loop

   /* putting current value_for_atr for corresponding attribute from look_up_table in temp variable*/
        select value_for_atr into temp_val from 
         (
          select value_for_atr, rownum rwn
          from look_up_table
        where ATTRIBUTE = temp_atr_val
         ) where rwn = ind;


      select name_of_col into temp_name from 
      (
      select name_of_col, rownum rwn
      from look_up_table
       where ATTRIBUTE = temp_atr_val
      /* and VALUE_FOR_ATR = temp_val*/
       ) where rwn = ind;

 select count (STORE_id )into store_count from store_table;

 for ind in 1..column_count loop

  select store_id into temp_storeid from (
        select id_dmstore, rownum rwn
        from store_table
        order by store_id
        )
     where rwn = ind;

 select sum(net_sales_home) into temp_sales
 from input_table_1
 where temp_atr_val = temp_val
 and store_id = temp_storeid;


dbms_output.put_line (temp_sales);
 end loop; 
       /* SELECT SUM(CASE WHEN temp_atr_val = temp_val THEN net_sales_home ELSE 0 END) into temp_variable
       FROM schemafinal_1;

 dbms_output.put_line (temp_val);
*/
/*temp_variable := temp_variable/sales_store; */

EXECUTE IMMEDIATE 'ALTER TABLE SAR ADD ('||temp_name||' number)'; 
EXECUTE IMMEDIATE ' UPDATE SAR b 
SET b.'||temp_name||' = :temp_variable' using temp_variable;

END LOOP;
END LOOP;   
END;

Answer 1

如果您正在尝试创建一个新列来存储数据，并且看到每次在temp变量中出现新值时都会创建一个新列，为什么不尝试这样：创建两个新列，并将其命名为column_name和column value。这样，您可以存储列的名称以及将存储在其中的值稍后，要从该列中进行选择，而不是执行：

select column_name from table;

你会这样做：

select column_value from table where column_name = temp_variable;

如果我明白你想要做什么，当然......

为列的值选择一些值，该列的值存储在临时变量中

1 个答案: