Flatness and m-adic completions.

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Let $A$ be a Noetherian ring, and $M$ be an arbitary a module. It is well known, that $M$ is flat iff every localization by maximal ideals of $M$ is flat. Is it also true, if we consider m-adic completions instead of localizations?

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No. For instance, if $A=\mathbb{Z}$ and $M=\mathbb{Q}/\mathbb{Z}$, then the completion of $M$ at every maximal ideal is trivial (since $M$ is divisible), but $M$ is not flat.