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Not All Cursors are Bad

Erik Darling doesn’t want to mess with your cursors (that much):

Read the code. Understand the requirements.

I tune queries all day long. The number of times someone has said THIS CURSOR IS A REAL BIG PROBLEM and been right is pretty small.

Often, there was a tweak to the cursor options, or a tweak to the query the cursor was calling (or the indexes available to it) that made things run in a more immediate fashion. I want to tune queries, not wrestle with logic that no one understands. Old code is full of that.

I’ll grant the premise (and add my own case where a cursor was necessary to solve the problem), though I did work at one company where the entire product logic was driven by nested cursors 5 or 6 levels deep. Those were really big problems. I think you’ll find the problem most frequently in shops with a heavy dose of Oracle, as Oracle cursors do perform well.

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