Create MYSQL database in docker inside Jenkins

version: '3'
services: 
    jenkins:
        container_name: jenkins
        image: jenkins/jenkins
        ports: 
            - "8080:8080"
        volumes: 
            - "./jenkins_home:/var/jenkins_home"
        networks: 
            - net
    remote_host:
        container_name: remote-host
        image: remote-host
        build: 
            context: centos7
        networks: 
            - net
    centos1:
        container_name: centos1
        image: centos1
        build: 
            context: OS
        networks: 
            - net
    db_host:
        container_name: db
        image: mysql:5.7
        environment: 
            - "MYSQL_ROOT_PASSWORD=1234"
        volumes: 
            - "./db_data:/var/lib/mysql"
        networks: 
            - net
networks: 
    net: 

FROM centos:7
RUN yum -y install openssh-server passwd net-tools nmap
RUN useradd centos1 && \
    echo "1234" | passwd centos1 --stdin && \
    mkdir /home/centos1/.ssh && \
    chmod 700 /home/centos1/.ssh
COPY remote_key.pub /home/centos1/.ssh/authorized_keys
RUN chown centos1:centos1 -R /home/centos1/.ssh && \
    chmod 600 /home/centos1/.ssh/authorized_keys
RUN yum install -y initscripts && \
    /usr/sbin/sshd-keygen
RUN yum install -y mysql
RUN curl -O https://bootstrap.pypa.io/get-pip.py && \
    python get-pip.py && \
    pip install awscli --upgrade
CMD [ "/usr/sbin/sshd", "-D" ]

mysql -u root -h db_host -p
MySQL [(none)]> show databases;
MySQL [(none)]> create database test;
MySQL [(none)]> use test;
MySQL [test]> create table info (name varchar(30), lastname varchar(20), age int(3));
MySQL [test]> desc info;
MySQL [test]> insert into info values ('ricardo', 'vanco', 21);
MySQL [test]> select * info;