In addition to the aforementioned MySQL behaviour you should be aware of, another list pointing out flaws/quirks in MySQL.
Had I knew all this from the start, maybe the ride would had been in easy mode. You can’t shake off the dirty sensation of “I have made a terrible choice” if you have to explain these awful quirks of MySQL to every new programmer. In a way this is technical debt – you have to pay the cognitive burden to correctly use MySQL.
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