testing inequality with columns that can be null

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不思量自难忘°
不思量自难忘° 2021-02-05 14:48

So, I asked a question this morning, which I did not phrase correctly, so I got a lot of responses as to why NULL compared to anything will give NULL/FALSE.

My actual q

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  •  独厮守ぢ
    2021-02-05 15:42

    I would personally write out the expression you came up with, especially if the table is expected to grow large. Wrapping the columns in function calls hurts performance by making it so the engine can't use any indexes you have on those columns. Of course, in a small table, this may not be any sort of issue, but I still like to do it the explicit way just in case a table ends up growing.

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