Thanks a lot both of you.
Klaus, those examples you wrote are exactly what I needed. They answer all my questions, especially the one on how to store the database password and how to send data to the database. Your examples are very easy to understand. Thanks for spending time writing them.
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Would you have a recommendation on which online SQL services to go for? So far I am hesitating between Google SQL and Rackspace, but maybe some other choices would be better?
Thanks again.