title: Spring Boot, JPA and MySQL returns empty results
body: <p>Ok I'm new to Java Spring and I am simply trying to access some data from a MYSQL database. Unfortunately I can't seem to load any data - I'm sure it's a silly mistake. (I've followed a number of sources, including <a href="https://stackoverflow.com/questions/27981789/how-to-use-spring-boot-with-mysql-database-and-jpa">this one</a>)  </p>
  
  <p><strong>I am using:</strong> java spring-boot, mysql, jpa, gradle</p>
  
  <p>Here is my <code>build.gradle</code>: </p>
  
  <pre><code>buildscript {
      repositories {
          mavenCentral()
      }
      dependencies {
          classpath("org.springframework.boot:spring-boot-gradle-plugin:1.3.2.RELEASE")
      }
  }
  
  apply plugin: 'java'
  apply plugin: 'eclipse'
  apply plugin: 'idea'
  apply plugin: 'spring-boot'
  
  jar {
      baseName = 'gs-serving-web-content'
      version =  '0.1.0'
  }
  
  repositories {
      mavenCentral()
  }
  
  sourceCompatibility = 1.8
  targetCompatibility = 1.8
  
  dependencies {
      compile("org.springframework.boot:spring-boot-starter-web")
      compile("org.springframework.boot:spring-boot-starter-thymeleaf")
      compile("org.springframework.boot:spring-boot-starter-data-jpa")
  
      compile("com.h2database:h2") //I get embedded db error if I take this out
      testCompile("junit:junit")
      compile('mysql:mysql-connector-java:5.1.35')
  }
  
  task wrapper(type: Wrapper) {
      gradleVersion = '2.3'
  }
  </code></pre>
  
  <p>Controller: </p>
  
  <pre><code>@Controller
  public class PersonController {
      @Autowired
      private PersonRepository personRepository;
  
      @RequestMapping(value = "/hello", method = RequestMethod.GET)
  public String greeting(...){
      List&lt;Person&gt; allPeople = personRepository.findAll(); //this comes back with 0 values
      ...
  }
  </code></pre>
  
  <p>PersonRepository: </p>
  
  <pre><code>public interface PersonRepository extends JpaRepository&lt;Person, Long&gt; {
  List&lt;Person&gt; findAll(); //returns empty list
  
  //Person findByAge(int Age); //throws an exception if I leave this on: "...nested exception is java.lang.IllegalArgumentException: Could not create query metamodel for method public abstract hello.model.Person hello.repository.PersonRepository.findByAge(int)!"
  }
  </code></pre>
  
  <p>Person: </p>
  
  <pre><code>@Entity
  @Table(name="person")
  public class Person {
      @Id
      @GeneratedValue(strategy = GenerationType.AUTO)
      private long PersonID;
      private String Firstname;
      private String Lastname;
      private int Age;
      //getters and setters
  }
  </code></pre>
  
  <p>Application.yaml</p>
  
  <pre><code>spring:
   datasource:
    url: jdbc:mysql://localhost:3306/datatest
    username: root
    password: ***
    driverClassName: com.mysql.jdbc.Driver
  </code></pre>
  
  <p>I've connected intelliJ successfully to MySQL database (under database tab)
  <a href="https://i.stack.imgur.com/778J1.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/778J1.jpg" alt="enter image description here"></a>
  and I can query it fine from the tab, but I can't load up the data through spring. There's got to be something wrong with my setup considering I can't seem to remove the embedded h2 database without an exception, nor can I add <code>findByAge</code>, <code>findByFirstname</code> etc combinations (all throw exceptions). </p>
  
  <p><strong>Update 1:</strong> I've applied hd1's changes to the Person class but I'm still not getting any data back: </p>
  
  <pre><code>@Entity
  @Table(name="person")
  public class Person {
      @Id
      @GeneratedValue(strategy = GenerationType.AUTO)
      private long personID;
      private String firstName;
      private String lastName;
      private int age;
      //getters and setters updated
  </code></pre>
  
  <p>PersonRepository: </p>
  
  <pre><code>List&lt;Person&gt; findAll();
  Person findByAge(int age); //no more errors here, but returns null
  Person findByLastName(String lastName);  //no more errors here, but returns null
  </code></pre>
  
  <p><a href="https://gist.github.com/gudthing/d29c377bd64cd639461f" rel="nofollow noreferrer">Full Runlog file</a> </p>
  
  <p><strong>Update 2:</strong> the controller method: </p>
  
  <pre><code>@RequestMapping(value = "/hello", method = RequestMethod.GET)
  public String greeting(@RequestParam(value = "name", required = false, defaultValue = "world") String name, Model model) {
      List&lt;Person&gt; allPeople = personRepository.findAll();
          ...
      System.out.print(allPeople.size()); //always 0, but I have many entries in db
  
      //if I try to create and save new entry in the db: 
      Person person = new Person();
      person.setFirstName("New");
      person.setLastName("Person");
      person.setAge(99);
      personRepository.save(person); //does not show up in DB, why?
      return "greeting";
  }
  </code></pre>