SQL - 如何通過涉及多列的計算獲得每行的最大值

Question

Table1 的每一行都應在計算中找到包含 Table1 和 Table2 中多列的最大值。 Table1 由列組成：ID、Code、Value1、Value2、Max_value Table2 由列組成：ID、Code、Perc1、Perc2

**Table1**

ID=1 (value1=1000, Value2=5000, Code=21);   Max_Value=? 
ID=2 (value1=2000, Value2=4000, Code=21);   Max_Value=?
ID=3 (value1=1000, Value2=5000, Code=21);   Max_Value=?

**Table2**

ID=25 (Perc1=5.2%, Perc2=3.5%, Code=21);    
ID=26 (Perc1=3.1%, Perc2=8.6%, Code=21);   
ID=27 (Perc1=2.5%, Perc2=3.4%, Code=21)


** Calculation**

formula:
    𝑀𝑎𝑥𝑉𝑎𝑙𝑢𝑒=𝑀𝐴𝑋[(𝑉𝑎𝑙𝑢𝑒1 ∗ 𝑃𝑒𝑟𝑐1)+(𝑉𝑎𝑙𝑢𝑒2 ∗ 𝑃𝑒𝑟𝑐2)]
              WHERE Table1.Code = Table2.Code

Max_Value (Table1.Id=1, Table2.Id=25) = 227
Max_Value (Table1.Id=1, Table2.Id=26) = 461 (max for ID 1)
Max_Value (Table1.Id=1, Table2.Id=27) = 195

Max_Value (Table1.Id=2, Table2.Id=25) = 224
Max_Value (Table1.Id=2, Table2.Id=26) = 406 (max for ID 2)
Max_Value (Table1.Id=2, Table2.Id=27) = 186

Max_Value (Table1.Id=3, Table2.Id=25) = 401
Max_Value (Table1.Id=3, Table2.Id=26) = 695 (max for ID 3)
Max_Value (Table1.Id=3, Table2.Id=27) = 313

Answer 1

如果我理解正確，你想要join和row_number() ：

select t12.*
from (select t1.*, t2.*,
             (t2.perc1 * t1.value1 + t2.perc2 * t1.value2) as calc,
             row_number() over (partition by t1.id order by (t2.perc1 * t1.value1 + t2.perc2 * t1.value2) desc) as seqnum
      from table1 t1 join
           table2 t2
           on t1.code = t2.code
     ) t12
where seqnum = 1;

您的公式和解釋暗示了table1的code列，盡管我在示例數據中沒有看到它。