Lately, I worked on several queries which started returning wrong results after upgrading MySQL Server to version 5.7 The reason for the failure was derived merge optimization which is one of the default [crayon-5bad99e6e350d113982083-i/]  options. Issues were solved, though at the price of performance, when we turned it [crayon-5bad99e6e3514554416742-i/] . But, more importantly, we could not [&]

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https://www.percona.com/blog/2018/09/25/why-optimization-derived_merge-can-break-your-queries/