В примерах используеться датаконтекст подключения к базе Northwind.
INNER JOIN:
var q1 = from c in dataContext.Customers
join o in dataContext.Orders on c.CustomerID equals o.CustomerID
select new
{
c.CustomerID,
c.ContactName,
o.OrderID,
o.OrderDate
};
join o in dataContext.Orders on c.CustomerID equals o.CustomerID
select new
{
c.CustomerID,
c.ContactName,
o.OrderID,
o.OrderDate
};
LEFT OUTER JOIN:
var q2 = from c in dataContext.Customers
join o in dataContext.Orders on c.CustomerID equals o.CustomerID into g
from a in g.DefaultIfEmpty()
select new
{
c.CustomerID,
c.ContactName,
a.OrderID,
a.OrderDate
};
join o in dataContext.Orders on c.CustomerID equals o.CustomerID into g
from a in g.DefaultIfEmpty()
select new
{
c.CustomerID,
c.ContactName,
a.OrderID,
a.OrderDate
};
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