Hugo Kornelis (12/6/2011)
The few timies where I did choose to use nested joins in actual code, I have always used parentheses and indentation for easier reading. In fact, my first draft of this question did use exactly that. I just took it out before submitting the question, because I am mean.:Whistling:
Yes you are mean! :laugh:
Actually, I think I rather misunderstood the point of the question. I thought you were intending to illustrate SQL/relational equivalences or something like that, but I now see you were aiming at the 'nested join' idea. I'll have to think about that a bit more to see if I understand the point completely.
Hugo Kornelis (12/6/2011)
I stiill stand by what I intended to write - that the only way to rewrite the query to a form that doesn't use nested joins involves reordering the table order and changing the left outer join to the far less cocmmon and harder to grasp right outer join form.
Hmm - but doesn't the CTE/derived table example break that assertion? Or are they still 'nested joins' somehow. I think that's the point I'm struggling with - what precisely 'nested joins' means.
Paul White
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