LINQ to SQL vs. ADO.NET – A Comparison - Wriju's BLOG - Site Home

ADO.NET is our contemporary data access component and now we have written many applications. Now there has been a lot of talk on LINQ to SQL. So we are little skeptical about this component and trying to find some relation between existing ADO.NET technology.

Purpose of this post is to give some quick brief on some major differences between ADO.Net and LINQ to SQL. I have not used 100% code as this is just to give an idea. The database I have used here is Northwind (SQL Server 2000 Sample database).

Some comparison,

Scenario 1

+++++++

Establishing connection between database and application,

ADO.NET

using(SqlConnection conn = new SqlConnection("Connection String"))

{

conn.Open();

}

LINQ to SQL

You create a .dbml file and give a name (assume “NW.dml”). Then there will be a DataContext class created. So you need to initialize the instance of an object.

NWDataContext db = new NWDataContext("Connection String");

You do not need to call any Open() method. Datacontext handles well the open and close method.

Scenario 2

+++++++

Getting data from database,

ADO.NET

using(SqlConnection conn = new SqlConnection("Connection String"))

{

using (SqlCommand comm = new SqlCommand("Select * from Customers"))

{

conn.Open();

SqlDataReader reader = comm.ExecuteReader();

DataTable dt = new DataTable("New Table");

dt.Load(reader);

}

LINQ to SQL

using (NorthwindDataContext db = new NorthwindDataContext())

{

//You can also use "var" at "IEnumerable<Customer>"

IEnumerable<Customer> custs = from c in db.Customers

select c;

foreach (Customer c in custs)

{

Console.WriteLine(c.CompanyName);

}

WOW!!! I have received comment from our Senior Program Manager Dinesh Kulkarni from LINQ to SQL team when I requested him to visit my blog. He mentioned,

DataTable provides you a cache that can be re-enumerated without DB roundtrip while LINQ to SQL results need to be explicitly cached with something like a ToList()/ToArray(). Identity caching in DataContext aside, the L2S code is closer to enumerating a DataReader. Although DataReader does not allow you to re-enumerate and requires another ExecuteReader, the impact of reenumerating L2S query is the same – another roundtrip to DB.

Scenario 3

+++++++

Inserting into the database,

ADO.NET

using(SqlConnection conn = new SqlConnection())

{

conn.Open();

SqlCommand comm = new SqlCommand("INSERT INTO...", conn);

comm.ExecuteNonQuery();

}

LINQ to SQL

using (NorthwindDataContext db = new NorthwindDataContext())