Question

我需要一些基本的SQL帮助...... 这是问题所在：在第一张表中我有

ID (primary key) 
data column (varchar)

包含产品，其他我有

ID (primary) 
second ID (foreign key) //references to ID from first table
price (decimal 8,2)

我需要的是从第二个表中的SUM价格来对应第一个表中的产品。它也应该保存为视图。 任何帮助？

Answer 1

JOIN这两个表格GROUP BY和汇总函数SUM是这样的：

CREATE VIEW DataPrices
AS
    SELECT 
      p.id,
      p.data,
      SUM(t.price) 
    FROM products p
    INNER JOIN secondtable t ON p.ID = t.ForeignKeyToTable1
    GROUP BY p.Id, p.data;

Answer 2

select table1.id, table1.data, sum(table2.price) as `total`
from   table1 inner join table2  
         on table1.id = table2.foreignkeyId
group  by table1.id, table1.data

两个表的sql sum

2 个答案: