Zebradillo

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Spotify analogy doesn't work

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So, why do I hate this so much. It looks like a great idea, it really does - what use is *just* a wheel? Or a car without a steering wheel? All the stages of development seem reasonable.  But there's a problem. What were the requirements? A car meets a very wide range of requirements, a skateboard just a few specific ones.  What if the most important requirement was to be able to carry 3 large suitcases and 4 people 200 miles?  What's the first "prototype" there? What's the first step then?  It's beguiling and misleading to present this as it's SUCH a narrow focus of what the requirements are and what the customer will actually be able to use as the product develops. Interestingly the picture is called "prototype".  And the end product is a car. Find me ONE car maker whose first prototype is a skateboard. So how do car manufacturers prototype?  They may create the basic chassis with no shell and make sure that the manufacturing process w...
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Non-cursor cursors

So I've been doing SQL queries for a while now, but only just worked out that 99 times out of 100, whenever you think you need a cursor, you probably don't. You probably need some sort of loop and some sort of track of where you are...but the answer to that is NOT a cursor. For example: You have a list of portfolios that you wish to value, but you need to call a proc/function against each in turn, so doing a single query is out of the question. The answer would appear to be a cursor, iterating over a list. WRONG. Here's how NOT to do it: DECLARE pfo_cursor CURSOR FOR SELECT pfo FROM #id OPEN pfo_cursor FETCH NEXT FROM pfo_cursor INTO @pfoLoop WHILE @@FETCH_STATUS = 0 ...do stuff with @pfoLoop FETCH NEXT FROM pfo_cursor INTO @pfoLoop CLOSE DEALLOCATE And here's a quicker, easier, cheaper, better way: SET @pfoLoop = (SELECT TOP 1 pfo FROM #id ORDER BY pfo) WHILE @pfoLoop is not null BEGIN ...do stuff with @pfoLoop SET @pfoLoop = (...
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