calculate time difference

Question

I'm try to us the following code string timespent1 = SELECT DATEDIFF(minute departureTimeentryTime) AS timespent FROM mambo where plateno = ' + TextBox1.Text + '; SqlCommand comman = new SqlCommand(timespent1 conn); comman.Parameters.AddWithValue(@timespent ToString()); comman.ExecuteNonQuery(); where departureTime is the departure time and entryTime is the entry time both in data type of datetime unfortunately is returnining a null value in the database.

Manas Mohapatra · Answer

You need to do as per following code: string timespent1=SELECT DATEDIFF(minutedepartureTimeentryTime)AS timespent FROM mambo where plateno=@plateNo; SqlCommand comman= new SqlCommand(timespent1conn); comman.Parameters.AddWithValue(@plateNoTextBox1.Text); SqlDataReader reader=comman.ExecuteReader(); while (reader.Read()) { Console.WriteLine(reader[0])); } Note: Always use parameterized query to avoid SQL injection.

Suthish Nair · Answer

Hi Simon is this a duplicate post or different? http://www.c-sharpcorner.com/Forums/time-difference3

ali tuncer · Answer

DATEDIFF will return null if one or both columns(departureTimeentryTime) have null values..

simon macharia · Answer

I have tried the code given below but still returning a null value in the column timespent in database