When you're designing applications that work with databases over the Internet, perhaps the largest problem you face is ensuring that everything can actually connect to everything else. You need to ensure that your users have a valid connection to the Net, and you need to ensure that your database server is up and running.
It's not a typically easy process--and it's a topic that attracts an unusually large amount of error handling code.
However, why not take the simple route and avoid potential big errors later on by checking whether your SQL Server is available to the user before starting your database code?
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