Added README.md and Dockerfile for mariadb container images

databases/mariadb/README.md

+
+
+# Runnning Mariadb as docker
+
+
+
+* After CLoning this repo, go to mariadb folder under databases.
+* Run following command to build the docker image.
+
+`docker build -t my-custom-db -f db.Dockerfile .`
+
+* The build image can be seen in the docker images list with below command.
+
+`docker image ls`
+
+* Now create the docker container, also pass the necessary environment variables for initial settings. Following command is given as example.
+
+`docker run -d --name my-custom-db -p 3306:3306 -e MYSQL_ROOT_PASSWORD=YOUR_ROOT_PASSWORD -e MYSQL_DATABASE=Devops -e MYSQL_USER=admin -e MYSQL_PASSWORD=YOUR_USER_PASSWORD db1`
+
+* MariaDB docker container is up and running. 
\ No newline at end of file

databases/mariadb/mariadb.Dockerfile

+# syntax=docker/dockerfile:1
+
+FROM mariadb:focal
+
+#Initialize and pre-populate the table from queries written in mytable.sql 
+COPY mytable.sql /docker-entrypoint-initdb.d/
+
+#can be moved to docker run command and optionally docker-compose
+VOLUME [ "/var/lib/mysql" ]
+
+EXPOSE 3306
\ No newline at end of file