WL#1685: optimize update/delete when we don't have to read old row
Affects: Server-7.1 — Status: Complete — Priority: Medium
We should optimize DELETE/UPDATE to not read rows before doing the delete/update for some trivial but common DELETE/UPDATE statements. This allows NDB to do some operations more efficently This could also help to fix bugs or unnecessary deadlocks in InnoDB INSERT…ON DUPLICATE KEY UPDATE. This might also be useful for WL#148 ON (UPDATE|DELETE) (CASCADE|SET NULL). See also WL#2442: Batched operation of multi UPDATE statements This has already been implemented in MySQL Server, it's called rbwr(read before write removal). This WL is most likely a duplicate or has been resurrected.. a scary zombie.
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