Question

在Microsoft SQL Server 2012上的数据库中从Java创建表。除一个表外，将创建所有表。我正在使用JPA并且有我的persistence.xml：

<?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="teknikPU" transaction-type="JTA">
    <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
    <jta-data-source>jdbc/teknikNDataSource</jta-data-source>
    <class>com.royken.entities.Bloc</class>
    <class>com.royken.entities.Elements</class>
    <class>com.royken.entities.Organes</class>
    <class>com.royken.entities.SousOrganes</class>
    <class>com.royken.entities.Utilisateurs</class>
    <class>com.royken.entities.Zone</class>
    <class>com.royken.entities.Reponse</class>
    <exclude-unlisted-classes>true</exclude-unlisted-classes>
    <properties>
      <property name="eclipselink.ddl-generation" value="create-or-extend-tables"/>
      <property name="eclipselink.logging.level" value="OFF"/>
      <property name="eclipselink.cache.shared.default" value="false"/>
      <property name="eclipselink.query-results-cache" value="false"/>
      <!--            <property name="hibernate.dialect" value="org.hibernate.dialect.MySQL5Dialect"/>
            <property name="hibernate.show_sql" value="true"/>
            <property name="hibernate.transaction.jta.platform" value="org.hibernate.engine.transaction.jta.platform.internal.SunOneJtaPlatform" />
            <property name="hibernate.transaction.factory_class" value="org.hibernate.engine.transaction.internal.jta.JtaTransactionFactory"/>
            <property name="hibernate.hbm2ddl.auto" value="update"/>
            <property name="hibernate.classloading.use_current_tccl_as_parent" value="false"/>-->
      <!--<property name="javax.persistence.schema-generation.database.action" value="create"/> -->
      <property name="javax.persistence.schema-generation.database.action" value="create"/>
    </properties>
  </persistence-unit>
</persistence>

这是我定义课程的方式：

@Entity
@XmlRootElement(name = "elements")
@Table(name = "ELEMENTS")
@XmlAccessorType(XmlAccessType.FIELD)
public class Elements implements Serializable {

    private static final long serialVersionUID = 1L;
    @OneToMany(mappedBy = "elements")
    private List<Reponse> reponses;

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "ID")
    private Long id;

    @Version
    @Column(name = "VERSION")
    private int version;

    @Column(name = "NOM")
    private String nom;

    @Column(columnDefinition = "tinyint(1) default true", name = "HASBORNS")
    private boolean hasBorns;

    @Column(columnDefinition = "tinyint(1) default true", name = "CRITERIAALPHA")
    private boolean criteriaAlpha;

}

我已经定义了7个这样的表，但只创建了6个表，不创建Elements表。当我通过使用mysql数据库更改数据源（不更改代码的任何部分）时，我的所有表都创建得很好。可能是什么问题？下图显示了SQL Server中的结果，Elements表不存在。

Answer 1

在persistence.xml使用中：

<property name="eclipselink.deploy-on-startup" value="true" />

在您的代码中，您可以使用：

import javax.ejb.Stateless;
import entity.userEntity;
import javax.persistence.EntityManager;
import javax.persistence.NoResultException;
import javax.persistence.PersistenceContext;
import javax.persistence.Query;

寻找EntityManager

 @PersistenceContext
            private EntityManager entityManager;

然后像：

一样使用它

Query query = entityManager.createQuery("SELECT e FROM Elements e WHERE e.id= :idValue");
            query.setParameter("idValue", 1);
            Elements elements = null;
            try {
                elements = (Elements) query.getSingleResult();
} catch (NoResultException ex) {
                ex.printStackTrace();
            }

您可以参考this

如果这也无助于here

Answer 2

我找到了解决问题的方法。未创建实体表，因为SQL Server不接受 true 作为 hasborns 和 criteriaalpha 的默认值。此外，它现在不分配给 tinyint 类型的大小。因此它在表创建期间抛出错误。为了解决这个问题，我换了：

@Column(columnDefinition = "tinyint(1) default true", name = "HASBORNS")
private boolean hasBorns;

@Column(columnDefinition = "tinyint(1) default true", name = "CRITERIAALPHA")
private boolean criteriaAlpha;

使用：

@Column(columnDefinition = "BIT default 1", name = "HASBORNS", length = 1)
private boolean hasBorns ;

@Column(columnDefinition = "BIT default 1", name = "CRITERIAALPHA", length = 1)
private boolean criteriaAlpha ;

它有效

Hibernate：SQL Server数据库中的所有表都不是自动创建的

2 个答案: