Linq Query CRM 2011 (late bound)

Add references to the following three dlls in the project

The initialization code

Uri organizationUri = new Uri("http://CRM2011/Contoso/XRMServices/2011/Organization.svc");
Uri homeRealmUri = null;
ClientCredentials credentials = new ClientCredentials();
credentials.Windows.ClientCredential = new System.Net.NetworkCredential("administrator", "pass@word2", "contoso");
OrganizationServiceProxy orgProxy = new OrganizationServiceProxy(organizationUri, homeRealmUri, credentials, null);
// Get the IOrganizationService
IOrganizationService orgService = (IOrganizationService)orgProxy;
//Get OrganizationServiceContext -the organization service context class implements the IQueryable interface and
//a .NET Language-Integrated Query (LINQ) query provider so we can write LINQ queries against Microsoft Dynamics CRM data.
OrganizationServiceContext orgServiceContext = new OrganizationServiceContext(orgService);

1) Simple Select

// Get name,number and ownerid for all the account records
var queryAccount1 = from r in orgServiceContext.CreateQuery("account")
select new
{
AccountName = r["name"],
AccountNumber = r["accountnumber"],
Owner = (EntityReference)r["ownerid"]
};

foreach (var account in queryAccount1)
{
MessageBox.Show("Account Name :-" + account.AccountName.ToString() + " " +
" Account Number :-" + account.AccountNumber.ToString() +
" Account Owner Id :- " + account.Owner.Id.ToString());
}

2)Select with Where

var queryAccount2 = from r in orgServiceContext.CreateQuery("account")
where ((EntityReference)r["accountid"]).Id.Equals(new Guid("EFB29802-7283-E011-8259-00155D045710"))
select new
{
AccountName = r["name"],
AccountNumber = r["accountnumber"],
Owner = (EntityReference)r["ownerid"]
};

3) Select with 2 Where clause

var queryAccount3 = from r in orgServiceContext.CreateQuery("account")
where (r["name"].Equals("test account 2") && r["address1_postalcode"].Equals("382424"))
select new
{
AccountName = r["name"],
AccountNumber = r["accountnumber"],
Owner = (EntityReference)r["ownerid"]
};

4) Where operator supports the following String functions Contains, StartsWith, EndsWith, and Equals.

var queryContactwithFirstNameasNishant = from r in orgServiceContext.CreateQuery("contact")
where ((string)r["firstname"]).Contains("Nishant")
select new
{
FirstName = r["firstname"],
LastName = r["lastname"]
};

var queryContactStartsWithN = from r in orgServiceContext.CreateQuery("contact")
where ((string)r["firstname"]).StartsWith("N")
select new
{
FirstName = r["firstname"],
LastName = r["lastname"]
};