Docker commit not working properly

Hi all,
i am new to docker. i pulled mysql5.7 image from docker dub. using the image i build the container , i have created some databases and commited the container . using the same image and i ran new container i dont see any exisinting data and configuartion
i have follwed below steps:
docker commit ef8d029159e9 (container id) lnew/mysqldb:1.0 (new image name).

docker run -name=mysqlultimate (container name) -d lnew/mysqld:1.0(image).
i want to know that where i was doing wrong.