I had the same approach that you suggested but there is a problem with this... For example, if the phone and country are null, then the SQL that will be constructed will be: 
UPDATE table SET city = 'test_city', FROM ...

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This will be incorrect because of the comma after the 'test_city.'

I am not worried about SQL injection attack since this is really something internal and will not be exposed to the outside world.

In reply to Re^2: Flexible Update SQL by bichonfrise74
in thread Flexible Update SQL by bichonfrise74

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