coalesce(n) vs repartition(n) — which is accurate?

Question

Accepted Answer

repartition can increase/decrease with shuffle; coalesce typically reduces partitions with minimized shuffle — repartition shuffles freely; coalesce mostly shrinks partitions cheaper.

Answer

They are always identical including full shuffles

Answer

repartition never shuffles

Answer

coalesce always increases partitions via full shuffle

coalesce(n) vs repartition(n) — which is accurate?

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