Fetch data from mysql database into SAPUI5 application

Hi Experts,

I am trying to fetch data from mysql database into my SAPUI5 application. I follow blog OData producer using Apache Olingo with MySQL, JPA & Tomcat web server but I get an error "The entity has no primary key attribute defined" in Java Resources under the model. Can anyone please help me in solving the error. I attached a screen shot of the error.

Thanks

Himadri