Question

For an application I need to send personalized invitation emails to end-users every hour. Those users email-addresses, and the rest of their information are in the database.

• All users that have a bit
  Planned.IsPlannable set to True and
  have a Planned.DateStart and a
  Planned.DateEnd between a certain
  period are available for receiving an
  email message.
• There are about 350 messages to sent every hour.
• All information that
  must be included in the message is
  from the Database.
• The application is
  a .NET4.0 Console application, for data
  access I use Subsonic3.0.

There are at least two scenarios to choose from: retrieving the appropriate data via a

1:) View something like:

SELECT    [Computer].ComputerName, 
          [User].UserEmail, 
          [Planned].DateAvailable, 
          [Planned].DatePlanned
FROM      [Computer] 
INNER JOIN
          [Planned] ON [Computer.ComputerID] = [Planned.ComputerID] 
INNER JOIN
          [User] ON [Computer].UserID = [User].UserID
WHERE     (DATEDIFF(dd, GETDATE(), [Planned.DateAvailable]) < 10) 
          AND Planned.IsPlannable = 1

and compose, based on the results of this view, the appropriate messages in the C# code of this application.

2:) Compose the entire message on the sql-server in the view and return something like

[EmailTo]
[Subject]
[Body]

Then only iterate trough the results and create MailMessage Objects from it

in both cases I get the messages like:

foreach (vwGetInvitableComputer u in UserController.GetAllInvitableUsers())
{
    // where the usercontroller wraps the Subsonic logic.
    // the composition happens here
}

Iterate trough that in the C# code and just compose the mailmessage from that preformatted data.

What scenario is performance and resources wise to choose?

update: There is indeed text manipulation in the database in option 2. However, this is replacing three strings in the messagbody to the CompterName, DateStart and DateEnd.Perhaps, SQL-views are smart enough to spread the performance for this, while the c# code does it “when requested”?

Answer 1

First consideration: Can you envision a time when changing the emails format will become necessary? If not then it probably doesn’t matter.

Second consideration: Can you envision a time when the emails will require more manipulation than SQL is easily capable of delivering? If so then you definitely should choose C#.

Third consideration: How problematic would a redeploy be for the environment?

And finally an alternative option: Use C# for the message composition, but use a database or file based Template that can easily be updated.