鎖資料列(可讀/不可讀)
MySQL Document 14.5.2.4 Locking Reads
主要分為sharedLock與lockForUpdate:
sharedLock locks only for write, lockForUpdate also prevents them from being selected
Pessimistic Locking (SELECT ... FOR UPDATE)
談到pessimistic concurrency control(Lock row for read),實作上再Transaction內使用:
SELECT ... FOR UPDATE
則結果列將會被鎖定且不可讀,應用上可做不重複流水號等等。