Verified on Spark 2.2.
First copy file mysql-connector-java-5.1.40.jar into folder
$SPARK_HOME/jars. Then get the data in table table_name from
MySQL service 192.168.110.3:3306/avatar with:
url = "jdbc:mysql://192.168.110.3:3306/avatar"
df = spark_session.read.jdbc(url, table_name, properties={ 'user': username,
'password': password, 'driver': 'com.mysql.jdbc.Driver' })