何为同步通信？何为异步通信？各自的特点是什么？

A. The server's SQL mode determines how the server should behave when performing data validation check and interpreting different forms of syntax
B. The server's SQL mode determines whether the server should be read-only or should accept commands such as INSERT and UPDATE
C. The server's SQL mode can be changed at the session level with a SET SESSION sql_mode="new_value" command
D. The server's SQL mode, when globally set on a slave server, applies to events sent from the master

A. 无间隙
B. 有续流
C. 有串联间隙
D. 有并联间隙

A. 正确
B. 错误

A. 保持乐观
B. 避免情志过激
C. 心理治疗
D. 静养心神