private static void LeftJoin()
{
using (ArtcomDBEntities1 db = new ArtcomDBEntities1())
{
var query = from c in db.Customers
join o in db.Orders on c.CustomerId equals o.CustomerId
into qo
from oJoined in qo.DefaultIfEmpty()
join op in db.OrderProducts on oJoined.OrderId equals op.OrderId
into qop
from opJoined in qop.DefaultIfEmpty()
join p in db.Products on opJoined.ProductId equals p.ProductId
into qp
from pJoined in qp.DefaultIfEmpty()
select new
{
CusName = c.CustomerName,
ProdName = pJoined.ProductName,
ProdCount = opJoined == null ? 0 : opJoined.Count,
Date = oJoined.Date.ToString()
};
foreach (var q in query)
{
Console.WriteLine("Customer: {0}\tProduct: {1}\tCount: {2}\tDate: {3}", q.CusName, q.ProdName, q.ProdCount, q.Date);
}
Console.WriteLine();
}
}
private static void GetCust()
{
using (ArtcomDBEntities1 db = new ArtcomDBEntities1())
{
var query = from c in db.Customers
select c;
foreach (var c in query)
{
Console.WriteLine("ID: {0}\tName: {1}", c.CustomerId, c.CustomerName);
}
Console.WriteLine();
}
}
private static void GetOrdDate()
{
using (ArtcomDBEntities1 db = new ArtcomDBEntities1())
{
var query = from o in db.Orders
join c in db.Customers on o.CustomerId equals c.CustomerId
where o.Date == DateTime.Today
select new
{
Oid = o.OrderId,
CustName = c.CustomerName,
Date = o.Date
};
foreach (var o in query)
{
Console.WriteLine("OID: {0}\tCID: {1}\tDate: {2}", o.Oid, o.CustName, o.Date);
}
Console.WriteLine();
}
}
private static void Join()
{
using (ArtcomDBEntities1 db = new ArtcomDBEntities1())
{
var query = from c in db.Customers
join o in db.Orders on c.CustomerId equals o.CustomerId
join op in db.OrderProducts on o.OrderId equals op.OrderId
join p in db.Products on op.ProductId equals p.ProductId
select new
{
CusName = c.CustomerName,
ProdName = p.ProductName,
ProdCount = op.Count
};
foreach (var q in query)
{
Console.WriteLine("Customer: {0}\tProduct: {1}\tCount: {2}", q.CusName, q.ProdName, q.ProdCount);
}
Console.WriteLine();
}
}
