static void Main(string[] args)
{
string connection = ConfigurationManager.ConnectionStrings["FHConnectionString"].ConnectionString;
string[] parameters = new string[] { "@Date" };
SqlDbType[] paramTypes = new SqlDbType[] { SqlDbType.Date };
string[] paramValues = new string[1];
DateTime firstDay = DateTime.Today;
string[] days = new string[] { "Mon", "Tue", "Wed", "Thu", "Fri" };
DateTime[] dates = new DateTime[5];
string updateCommand = @"UPDATE Meals
SET [Dinner] = ISNULL(NULLIF(Dinner,''), {0}Dinner)
,[Lunch] = ISNULL(NULLIF(Lunch,''), {0}Lunch)
,[LQty] = CASE WHEN Lunch = '' THEN 1 ELSE LQty END
,[DQty] = CASE WHEN Dinner = '' THEN 1 ELSE DQty END
FROM
[dbo].[Meals] AS Meals
INNER JOIN [dbo].[WeeklyMeals] AS Weekly
ON Meals.UserID = Weekly.UserID
WHERE [Date] = @DATE";
string insertCommand = @"INSERT INTO Meals ([UserID], [Dinner], [Lunch], [LQty], [DQty], [Date])
SELECT UserID AS ID, {0}Dinner AS Dinner, {0}Lunch AS Lunch, 1 AS LQty, 1 AS DQty, @Date AS Date
FROM
[dbo].[WeeklyMeals] AS Weekly
WHERE NOT EXISTS (SELECT * FROM Meals WHERE UserID = Weekly.UserID AND Date = @Date)" ;
// Run the command
SqlTools.ExecuteNonQuery(connection, String.Format(updateCommand, days[(int)firstDay.DayOfWeek - 1]), parameters, paramTypes, new string[] { firstDay.ToString("yyyy-MM-dd") });
SqlTools.ExecuteNonQuery(connection, String.Format(insertCommand, days[(int)firstDay.DayOfWeek - 1]), parameters, paramTypes, new string[] { firstDay.ToString("yyyy-MM-dd") });
}