Atesz <atesz@xxxxxxxx> writes: > My question: Why need this strict locking? > In my opinion there isn't exclusion between the DROP CONSTRAINT and the > SELECT. This isn't going to be changed, because the likely direction of future development is that the planner will start making use of constraints even for SELECT queries. This means that a DROP CONSTRAINT operation could invalidate the plan of a SELECT query, so the locking will be essential. regards, tom lane
