"Installing" MySQL JDBC .jar file for MATLAB
MATLAB requires the directory and filename be added to the javaclasspath.  Litmus test:

&gt;&gt; javaclasspath('-static')
        STATIC JAVA PATH
/Library/Java/Extensions/mysql-connector-java-5.1.46-bin.jar                                               
/Library/Java/Extensions/mysql-connector-java-5.1.46.jar  


Instructions for adding the .jar files to the class path:


Run the prefdir command in the Command Window. The output of this command is a file path to the MATLAB® preferences folder on your computer. 
Close MATLAB.
Navigate to the folder from step 1, and create a file named javaclasspath.txt in the folder.
Open javaclasspath.txt. Add the full path to the database driver JAR file in javaclasspath.txt. The full path includes the path to the folder where you downloaded the JAR file from the database provider followed by the JAR file name. The following is an example of the path: 


/home/user/DB_Drivers/mysql-connector-java-5.1.17-bin.jar. 

Save and close javaclasspath.txt.
Restart MATLAB.