发出MQTT的CONNECT请求时候,需要提供下面哪些参数:
A: clientId;
B: UserName;
C: Password;
D: port;
A: clientId;
B: UserName;
C: Password;
D: port;
举一反三
- 使用mysql扩展连接 MySql 数据库的正确语法是? A: mysql_connect($username, $password) B: connect_mysql($username, $password) C: mysql_connect($servername, $username, $password) D: mysql::connect($servername, $username, $password)
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