Don't use non-unique indexes as functional dependencies in AND expressions.#2868
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Don't use non-unique indexes as functional dependencies in AND expressions.#2868
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max-hoffman
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I suspect the change here is upstream of the root cause, but it's directionally correct and i agree the plan change is more of a testing artifact than a regression customers using statistics would see
This was referenced Mar 4, 2025
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This fixes a customer issue that was causing
Error 1105 (HY000): result max1Row iterator returned more than one rowWe can probably do better than this: we could tweak it so that adding a FD key on a non-unique index instead adds an implication that the non-unique index key determines the primary key.
But this is a simpler fix in the meantime that makes us more correct.