Which one will run faster?

Question

Possible Duplicate:
Is datareader quicker than dataset when populating a datatable?

 public DataTable GetReviewsId(Objects myObjects)
 {
     DataTable tblBindReviews = new DataTable();
     string Query = "";
     try
     {
         Query = "select distinct ProductId from tblReview where ProductId in (select ProductId from tblProduct where R=0 and T=0)";
         /*SqlConnection mySqlConnection = this.SetDatabaseConnection();
         SqlDataAdapter mySqlDataAdapter = new SqlDataAdapter(Query, mySqlConnection);
         mySqlDataAdapter.Fill(tblBindReviews);*/
         /*mySqlConnection.Open();
         SqlCommand cmd = new SqlCommand(Query,mySqlConnection);
         tblBindReviews.Load(cmd.ExecuteReader());*/
     }
     catch (SqlException ex)
     {
         throw new Exception(ex.Message);
     }
     finally
     {
         this.ClosedatabaseConnection();
     }
     return tblBindReviews;
 }

In the above code i have written two ways(each inside the commented part) of retrieving data, one using data adapter and the other using datareader. which one of the two will run faster?

Have you run a test over your sample data set? `System.Diagnostics.Stopwatch` is your friend for these types of questions. — jheddings, Oct 10 '12 at 13:05
What makes you think there is even a difference between the two options? — Security Hound, Oct 10 '12 at 13:06
i tried but they seem to give me the same result while debugging using visual studio 2010.. — Niar, Oct 10 '12 at 13:08
Use a larger data set or run your test inside a loop. If you are concerned about Debug vs Release, try on both. If you get the same or undistinguishable performance, then which one is probably up to you. — jheddings, Oct 10 '12 at 13:08
@jheddings..can you tell me how i can use the System.Diagnostics.Stopwatch ..can i just include it in my code — Niar, Oct 10 '12 at 13:09
The docs have a nice example: http://msdn.microsoft.com/en-us/library/system.diagnostics.stopwatch.aspx Of course, instead of sleeping, you would access your database. — jheddings, Oct 10 '12 at 13:11

pero · Answer 1 · 2012-10-10T13:11:32.113

3

DataReader is the fastest way. In any case faster then DataAdapter as DataAdapter uses DataReaders inside and performs additional operations (works with datasets multiple tables, .....)

DbDataAdapter - FillInternalMethod

edited Oct 10 '12 at 13:11

answered Oct 10 '12 at 13:06

pero

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How can you make this claim considering how simple the query is? – Security Hound Oct 10 '12 at 13:07

score 1 · Answer 2 · answered Oct 10 '12 at 13:06

If you execute select operations i suggets you to use SqlDataReader

Only has one record in memory at a time rather than an entire result set

Is about as fast as it you can get for that one iteration

Allows you start processing results sooner

Nota :

With SqlDataAdapter you have Much higher memory use, you wait until all the data is loaded before using any of it

Which one will run faster?

2 Answers2