hard20 pts · first answer countsconcurrencyapi-designsql

Two agents edit one ticket

Two support agents open the same ticket. Agent A saves a status change, then agent B saves an edited description, silently overwriting A’s change with old data. What is the standard fix?

A.Lock the database row from the moment the edit form opens until it is savedB.Use last-write-wins based on the client clockC.Push updates over WebSockets so agents never conflictD.Add a version column, update WHERE id = $1 AND version = $2, and return 409 so the client can reload or merge when no row matches

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