两个表的sql sum

Question

I need help with some basic sql... here is the problem: In first table I have

ID (primary key) 
data column (varchar) 

which contains products, in other I have

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

What I need is to SUM price from second table that corresponds products from first table. also it should be saved as view. any help?

Answer 1

JOIN the two tables, with GROUP BY and an aggregate function SUM like this:

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