Think of it this way. If your wife wants you
to fold the washing that's come out of the tumble dryer - she might
well say 'can you please fold the washing?'. That's a set based approach
- it's an operation over a collection of items.
The cursor based approach would be the equivalent of your wife asking you to fold a t-shirt, then when you had come back with that asking you to fold a pair of trousers, then when you had come back with that, asking if you could fold a jumper. No doubt, that would really hack you off. SQL Server doesn't fare much better, and really prefers to be asked to do things the set based way.
When working in T-SQL, try to tell the system what you want to do with the data, not how you want it done.
The cursor based approach would be the equivalent of your wife asking you to fold a t-shirt, then when you had come back with that asking you to fold a pair of trousers, then when you had come back with that, asking if you could fold a jumper. No doubt, that would really hack you off. SQL Server doesn't fare much better, and really prefers to be asked to do things the set based way.
When working in T-SQL, try to tell the system what you want to do with the data, not how you want it done.
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