我有一个在 JDBC 和 MySQL 上使用 Hibernate 的 JPA 应用程序，没有任何应用程序服务器。

在我的 persistence.xml 中，我定义了从脚本创建、加载和删除数据库的规则:

<property name="javax.persistence.schema-generation.database.action" value="drop-and-create"/>
<property name="javax.persistence.schema-generation.create-source" value="script"/>
<property name="javax.persistence.schema-generation.create-script-source" value="META-INF/scripts/create.sql" />
<property name="javax.persistence.sql-load-script-source" value="META-INF/scripts/load.sql" />
<property name="javax.persistence.schema-generation.drop-source" value="script" />
<property name="javax.persistence.schema-generation.drop-script-source" value="META-INF/scripts/drop.sql" />

但是，当执行 Maven 测试目标时，出现以下错误:

无法执行 JPA 架构生成创建命令 [CREATE TABLE country (]

堆栈跟踪看起来像这样:

Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:404)
at com.mysql.jdbc.Util.getInstance(Util.java:387)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:941)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3870)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3806)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2470)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2617)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2546)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2504)
at com.mysql.jdbc.StatementImpl.executeInternal(StatementImpl.java:840)
at com.mysql.jdbc.StatementImpl.execute(StatementImpl.java:740)
at org.hibernate.jpa.internal.schemagen.GenerationTargetToDatabase.acceptCreateCommands(GenerationTargetToDatabase.java:44)
... 34 more

加载脚本从创建国家表开始:

DROP DATABASE IF EXISTS bookstore;

CREATE DATABASE bookstore;

USE bookstore;

CREATE TABLE country (
    id          INT(10) UNSIGNED AUTO_INCREMENT NOT NULL,
    name        VARCHAR(50) NOT NULL,
    code        VARCHAR(2) NOT NULL UNIQUE,
    description VARCHAR(1000),
    KEY (id)
);
ALTER TABLE country ADD CONSTRAINT pk_country_id PRIMARY KEY (id);

Country类映射在persistence.xml文件中，其源代码如下。

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table(name = "country")
public class Country extends ro.pub.cs.aipi.lab02.entities.Entity {

    protected Long id;
    protected String name;
    protected String code;
    protected String description;

    public Country() {
    }

    public Country(String name, String code, String description) {
        this.name = name;
        this.code = code;
        this.description = description;
    }

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "id")
    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    @Column(name = "name")
    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    @Column(name = "code")
    public String getCode() {
        return code;
    }

    public void setCode(String code) {
        this.code = code;
    }   

    @Column(name = "description")
    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }
}

persistence.xml 文件中的 Hibernate 属性如下:

     <property name="hibernate.connection.pool_size" value="1"/>
     <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect"/>
     <property name="hibernate.format_sql" value="true" />
     <property name="hibernate.temp.use_jdbc_metadata_defaults" value="false"/>
     <property name="hibernate.id.new_generator_mappings" value="false"/>
     <property name="hibernate.hbm2ddl.auto" value="true"/>

我已经尝试将 hibernate.dialect 更改为 org.hibernate.dialect.MySQL5InnoDBDialect 并从 Entity 类中删除 @Table 注释，但我没有注意到行为有任何变化。

最佳答案

我终于弄明白了。 hibernate 似乎每行只需要一个语句，因为在我的例子中，脚本是格式化的，它只占用了语句的第一行，因此不完整。

重新格式化脚本并将命令放在一行中解决了问题。

关于java - 无法执行 JPA 架构生成创建命令，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/33270940/