问从.NET到smalldatetime的DateTime -如何查询？

EN

CREATE PROCEDURE [dbo].[ShowGivenSmallDateTimeValue] 
    @givenSmallDateTime smalldatetime
AS
BEGIN
    -- SET NOCOUNT ON added to prevent extra result sets from
    -- interfering with SELECT statements.
    SET NOCOUNT ON;

    -- Simply return the given small date time value back to sender.
    SELECT @givenSmallDateTime
END

var connectionBuilder = new SqlConnectionStringBuilder();
connectionBuilder.DataSource = "localhost\\sqlexpress";
connectionBuilder.IntegratedSecurity = true;

var now = DateTime.UtcNow;

using (var connection = new SqlConnection(connectionBuilder.ConnectionString))
using (var command = new SqlCommand())
{
    command.Connection = connection;
    command.CommandType = CommandType.StoredProcedure;
    command.CommandText = "ShowGivenSmallDateTimeValue";
    command.Parameters.Add(new SqlParameter("@givenSmallDateTime", SqlDbType.SmallDateTime) { Value = now });

    connection.Open();
    var result = (DateTime)command.ExecuteScalar();
    var difference = result - now;

    Console.WriteLine("Due to the smalldatetime roundings we have a difference of " + difference + ".");
}

            // Default conversion is now DateTime to datetime2. The ADO.Net default is to use datetime. 
            // This appears to be a safe change as any datetime parameter will accept a datetime2 so long as the value is within the
            // range for a datetime. Hence this code is acceptable for both datetime and datetime2 parameters, whereas datetime is not 
            // (because it doesn't handle the full range of datetime2).
            SqlParameter sqlParam = new SqlParameter(name, SqlDbType.DateTime2);