052-187

Which two statements describe good practices for an application developer to reduce locking conflicts in Oracle database? (Choose two.)
A.Avoid coding unnecessary long-running transactions.
B.Allow the database to handle locks in default locking mode.
C.Always explicitly code the locks as per the requirement of the application.
D.Allow escalation of row locks to block locks if too many row locks cause problem.

A 正确，长时间的事务占据资源，别的用户无法访问
B 正确，这样排队机制是自动运行的，不需要人来干预
C 错误，如果想修改锁还需要修改程序
D 错误，应该是解决锁冲突，而不是升级锁来阻止锁