left outer joins

[Nilish]

Hi, How should i use the left outer joins in LINQ VB.net

[Howard Richards]

Left outer joins are created using Group Join and the DefaultIfEmpty() Lets say I want all customers and any OrderIDs (even if customer has no orders). Using Northwind datacontext in db:

Dim query = From c In db.Customers _
Group Join o in db.Orders _
On c.CustomerID Equals o.CustomerID _
Into tmp = Group _
From t in tmp.DefaultIfEmpty _
Select New With { _
.Name = c.CompanyName, _
.OrderID =If(t is Nothing, _
"** no order **", _
CStr(t.OrderID)) }

The group join creates a list of the orders for each customer. DefaultIfEmpty specifies the outer-join part. This is will return '** no order **' if a customer has no orders, otherwise one row per order. Check out this article[^] for more help.

'Howard

[abdul manzoor]

like sql s server