How to perform innner Join on Five Tables using Linq

Are the types of your expression variables the same? E.g.: are c.GroupId and g.GroupId both int or is one of them of type byte?

The types of the variables in your expressions must be of the same type if you want to compare them with each other.

View the original article here

Select and summarize data from three tables

i have three tables

customer

id | name 1 | john

orders

id | customer_id | date1 | 1 | 2013-01-012 | 1 | 2013-02-013 | 2 | 2013-03-01

order_details

id | order_id | qty | cost1 | 1 | 2 | 102 | 1 | 5 | 103 | 2 | 2 | 104 | 2 | 2 | 155 | 3 | 3 | 156 | 3 | 3 | 15

i need to select data so i can get the output for each order_id the summary of the order sample output. I will query the database with a specific customer id

output

date | amount | qty | order_id2013-01-01 | 70 | 7 | 12013-02-01 | 50 | 4 | 2

this is what i tried

SELECT orders.id, orders.date, SUM(order_details.qty * order_details.cost) AS amount, SUM(order_details.qty) AS qtyFROM orders LEFT OUTER JOIN order_details ON order_details.order_id=orders.id AND orders.customer_id = 1 GROUP BY orders.date

but this returns the same rows for all customers, only that the qty and cost dont hav values

View the original article here