D:\mysql-8.0.15-winx64\bin>mysqld --defaults-file=D:\mysql-8.0.15-winx64\my.ini --initialize --console
2019-03-16T06:11:12.538350Z 0 [System] [MY-013169] [Server] D:\mysql-8.0.15-winx64\bin\mysqld.exe (mysqld 8.0.15) initializing of server in progress as process 11136
2019-03-16T06:11:32.301846Z 5 [Note] [MY-010454] [Server] A temporary password is generated for root@localhost: K)gt#U*D8b;a
2019-03-16T06:11:41.101367Z 0 [System] [MY-013170] [Server] D:\mysql-8.0.15-winx64\bin\mysqld.exe (mysqld 8.0.15) initializing of server has completed

提示：

Navicat 连接mysql 显示 Clinet dose not support authentication protocol request by server

 1 在命令窗口 输入mysql -uroot -p 首先通过cmd进入mysql 

2 更改加密方式 

mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'password' PASSWORD EXPIRE NEVER;

Query OK, 0 rows affected (0.10 sec)

3 更改密码

mysql> ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY '123';

Query OK, 0 rows affected (0.35 sec)

 这个密码是navicat链接mysql 的密码

4刷新

mysql> FLUSH PRIVILEGES;

Query OK, 0 rows affected (0.28 sec)