mysql backup dump docker file

Shell
docker run -it --rm --link my-old-database:mysql mysql sh -c 'echo "[client]\n host=\"$MYSQL_PORT_3306_TCP_ADDR\"\n user=root\n password=\"$MYSQL_ENV_MYSQL_ROOT_PASSWORD\"" > my.cnf && exec mysqldump --defaults-file=my.cnf --databases my_database_name' > db_dump.sql
Source

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