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Getting Started

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By using LINQ to SQL, you can use the LINQ technology to access SQL databases just as you would access an in-memory collection.

For example, the nw object in the following code is created to represent the Northwind database, the Customers table is targeted, the rows are filtered for Customers from London, and a string for CompanyName is selected for retrieval.

When the loop is executed, the collection of CompanyName values is retrieved.

// Northwnd inherits from System.Data.Linq.DataContext.
Northwnd nw = new Northwnd(@"northwnd.mdf");
// or, if you are not using SQL Server Express
// Northwnd nw = new Northwnd("Database=Northwind;Server=server_name;Integrated Security=SSPI");

var companyNameQuery =
    from cust in nw.Customers
    where cust.City == "London"
    select cust.CompanyName;

foreach (var customer in companyNameQuery)
{
    Console.WriteLine(customer);
}

' Northwnd inherits from System.Data.Linq.DataContext.
Dim nw As New Northwnd("c:\northwnd.mdf")
' or, if you are not using SQL Server Express
' Dim nw As New Northwnd("Database=Northwind;Server=dschwart7;Integrated Security=SSPI")

Dim companyNameQuery = _
    From cust In nw.Customers _
    Where cust.City = "London" _
    Select cust.CompanyName

For Each customer In companyNameQuery
    Console.WriteLine(customer)
Next

Next Steps

For some additional examples, including inserting and updating, see What You Can Do With LINQ to SQL.

Next, try some walkthroughs and tutorials to have a hands-on experience of using LINQ to SQL. See Learning by Walkthroughs.

Finally, learn how to get started on your own LINQ to SQL project by reading Typical Steps for Using LINQ to SQL.

See also