DataContext.GetCommand(IQueryable) Method

Definition

Namespace:

System.Data.Linq

Assembly:

System.Data.Linq.dll

Gets the information about SQL commands generated by LINQ to SQL.

public:
 System::Data::Common::DbCommand ^ GetCommand(System::Linq::IQueryable ^ query);

public System.Data.Common.DbCommand GetCommand (System.Linq.IQueryable query);

member this.GetCommand : System.Linq.IQueryable -> System.Data.Common.DbCommand

Public Function GetCommand (query As IQueryable) As DbCommand

Parameters

query

IQueryable

The query whose SQL command information is to be retrieved.

Returns

DbCommand

The requested command information object.

Examples

// using System.Data.Common;
Northwnd db = new Northwnd(@"c:\northwnd.mdf");

var q =
    from cust in db.Customers
    where cust.City == "London"
    select cust;

Console.WriteLine("Customers from London:");
foreach (var z in q)
{
    Console.WriteLine("\t {0}",z.ContactName);
}

DbCommand dc = db.GetCommand(q);
Console.WriteLine("\nCommand Text: \n{0}",dc.CommandText);
Console.WriteLine("\nCommand Type: {0}",dc.CommandType);
Console.WriteLine("\nConnection: {0}",dc.Connection);

Console.ReadLine();

' Imports System.Data.Common

Dim db As New Northwnd("c:\northwnd.mdf")

Dim q = _
From cust In db.Customers _
Where cust.City = "London" _
Select cust

Console.WriteLine("Customers from London:")
For Each z As Customer In q
    Console.WriteLine(vbTab & z.ContactName)
Next

Dim dc As DbCommand = db.GetCommand(q)
Console.WriteLine(Environment.NewLine & "Command Text: " & Environment.NewLine & dc.CommandText)
Console.WriteLine(Environment.NewLine & "Command Type: {0}", dc.CommandType)
Console.WriteLine(Environment.NewLine & "Connection: {0}", dc.Connection)

Console.ReadLine()

Remarks

This method is only a getter and does not affect DataContext state.

Note the following considerations:

• The argument must be non-null. Otherwise, a null argument exception is thrown.

• Normal query translation exceptions thrown during LINQ to SQL query execution apply for a query that cannot be translated.

• Only the first query command is returned. Specifically, additional commands that are used for eager loading (LoadWith) are not included.

• DataContext does not track what the user does with the command. For example, results from the execution of the returned command are not tracked and do not affect DataContext state.