Seeing this error, I went to Baidu and found that the format of the docker run command was incorrect. This error occurred because the run + name was wrong, capital letters could not appear, myTest was wrong, lowercase mytest was required.
There is another error:'-' is wrong, pay attention to the difference between full-width and half-width, so do not copy the command directly. Of course, the copied content may have different encoding formats.
docker run -p 3306:3306 --name mysql \
-v /mydata/mysql/log:/var/log/mysql
-v /mydata/mysql/data:/var/lib/mysql
-v /mydata/mysql/conf:/etc/mysql
-e MYSQL_ROOT_PASSWORD=root
-d mysql:5.7