Insert Datetime.now from asp.net into sql server

You're specifying a SqlDbType of Date - that doesn't have a time. So when the driver is converting the parameter value into the desired type, it's removing the time part.

You're also converting DateTime.Now into a string for no obvious reason... and doing so in a way which uses an odd and lossy time format (h:m:s, with no AM/PM designator). If you really did want to convert to a string, it would be better to use HH:mm:ss for the time specifier.

This line:

sqlComm.Parameters.Add("@join_date", SqlDbType.Date).Value = DateTime.Now.ToString("yyyy-MM-dd h:m:s");

should be:

sqlComm.Parameters.Add("@join_date", SqlDbType.DateTime).Value = DateTime.Now;