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How do I check if ExecuteScalar() returned me any rows when you are using casting this way...

Posted By:      Posted Date: September 23, 2010    Points: 0   Category :ASP.Net

Hi all

The code below works fine if I have records on my table but if the table is empty I get the following error:

latestTimeStamp1 = (DateTime)cmd.ExecuteScalar(); <=== {"Specified cast is not valid."}

So I am trying to add an IF statement to check if there was any return from ExecuteScalar() method.
How can I verify if something was returned or how can I prevent this cast error from happening?
I managed a workaround by using DataTable and checking if table was null but I need this code to have less overhead as possible since I will be pulling up this timeStamp date all the time.

 DateTime latestTimeStamp1 = DateTime.UtcNow;
 string select = "select max(timeStamp) from Table1";

 SqlConnection conn = new SqlConnection(WebConfigurationManager.ConnectionStrings["Test"].ConnectionString);
		 SqlCommand cmd = new SqlCommand(select, conn);

	//if ExecuteScalar returns something 
	 	latestTimeStamp1 = (DateTime)cmd.ExecuteScalar();
		return latestTimeStamp1;
 catch (Exception ex)

Thank you

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Hi all,

I know for a fact that the SQL statement below returns NULL but my code statement "if (obj != null)" is not working.
When I debug it I see a value of {} ... not sure what that is. Here is my code:

protected string GetLatestTimeStamp()
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