WARN [org.hibernate.engine.jdbc.spi.SqlExceptionHelper] SQL错误：0，SQLState：08003

Question

我正在使用JPA和Hibernate EntityManager连接到MySQL数据库。

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.1" xmlns="http://xmlns.jcp.org/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd">
    <persistence-unit name="TaraTicketEJB">
        <jta-data-source>java:jboss/datasources/TaraTicketDS</jta-data-source>
        <properties>
            <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect"/>
            <property name="hibernate.hbm2ddl.auto" value="create"/>
            <property name="hibernate.show_sql" value="true"/>
        </properties>
    </persistence-unit>
</persistence>

以下是服务方法：

@Stateless
@Remote(TicketDAO.class)
public class TicketBean implements TicketDAO{

    @PersistenceContext
    private EntityManager em;

    ...

    @Override
    public List<Ticket> getAllTickets() {
        return em.createNamedQuery(Ticket.QUERY_GETALL,Ticket.class).getResultList();
    }

}

这是实体：

@Entity
@NamedQuery(name=Ticket.QUERY_GETALL,query = "SELECT c FROM Ticket c")
public class Ticket implements Serializable{

    /**
     * 
     */
    private static final long serialVersionUID = 1L;

    public static final String QUERY_GETALL = "Ticket.GetAll";

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private int id; 

    @NotNull
    @Size(min=10,max=150)
    private String name;

    private String description;

    private String username;

    private Date date;

    ...more properties

    @Version
    private Timestamp lastChanged;

    ...getter and setter ;)


}

我在日志中看到一条警告“SQL Error：0，SQLState：08003”。

20:16:15,594 INFO  [stdout] (default task-33) Hibernate: select ticket0_.id as id1_0_, ticket0_.category as category2_0_, ticket0_.date as date3_0_, ticket0_.description as descript4_0_, ticket0_.email as email5_0_, ticket0_.lastChanged as lastChan6_0_, ticket0_.name as name7_0_, ticket0_.priority as priority8_0_, ticket0_.status as status9_0_, ticket0_.subject as subject10_0_, ticket0_.telephoneNumber as telepho11_0_, ticket0_.user as user12_0_, ticket0_.username as usernam13_0_ from Ticket ticket0_

20:16:15,596 WARN  [org.hibernate.engine.jdbc.spi.SqlExceptionHelper] (default task-33) SQL Error: 0, SQLState: 08003

这是什么意思？