为确保批量操作确实起作用,我使用Wireshark检查了我的数据包,发现它没有使用批量插入。
以下是其中一个插入数据包: 它没有执行:
INSERT INTO ENTITYCLASSTEST (LASTNAME, NAME) VALUES ('sfirosijfhgdoi 0', 'dsufius0'), ('sfirosijfhgdoi 0', 'dsufius0'), ('sfirosijfhgdoi 0', 'dsufius0'), ('sfirosijfhgdoi 0', 'dsufius0')... and so on
我原本希望它能够像上面描述的那样操作,但它是按照每个数据包插入一行而不是每个数据包插入多行。
这是我的实体类:
@Entity
public class EntityClassTest implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
private String name;
private String lastname;
public EntityClassTest() {
}
public EntityClassTest(Long id, String name, String lastname) {
this.id = id;
this.name = name;
this.lastname = lastname;
}
public EntityClassTest(String name, String lastname) {
this.name = name;
this.lastname = lastname;
}
public Long getId() {
return id;
}
public String getName() {
return name;
}
public String getLastName() {
return lastname;
}
public void setId(Long id) {
this.id = id;
}
public void setName(String name) {
this.name = name;
}
public void setLastName(String lastname) {
this.lastname = lastname;
}
@Override
public int hashCode() {
int hash = 0;
hash += (id != null ? id.hashCode() : 0);
return hash;
}
@Override
public boolean equals(Object object) {
// TODO: Warning - this method won't work in the case the id fields are not set
if (!(object instanceof EntityClassTest)) {
return false;
}
EntityClassTest other = (EntityClassTest) object;
if ((this.id == null && other.id != null) || (this.id != null && !this.id.equals(other.id))) {
return false;
}
return true;
}
@Override
public String toString() {
return "database.EntityClassTest [id=" + id + " ]";
}
}
这是我的持久化方法,它接收一个List
并持久化其中所有的对象。
public void insertListToTable(final String persistenceUnit, final List list) throws SQLException {
final EntityManagerFactory entityManagerFactory = Persistence.createEntityManagerFactory(persistenceUnit);
final EntityManager entityManager = entityManagerFactory.createEntityManager();
final EntityTransaction transaction = entityManager.getTransaction();
try {
final int listSize = list.size();
transaction.begin();
for (int i = 0; i<listSize; i++) { //Object object : list) {
final Object object = list.get(i);
entityManager.persist(object);
if ( i % 500 == 0 ) { //500, same as the JDBC batch size defined in the persistence.xml
//flush a batch of inserts and release memory:
entityManager.flush();
entityManager.clear();
}
}
transaction.commit();
}
catch(Exception e) {
if (transaction != null) {
transaction.rollback();
}
throw new SQLException(e.getMessage());
}
finally {
entityManager.close();
}
}
我的 persistence.xml
文件中,我将批处理值设置为 500,文件内容如下:
<?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="ExternalServer" transaction-type="RESOURCE_LOCAL">
<provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
<!-- List of Entity classes -->
<class>model.EntityClassTest</class>
<properties>
<property name="javax.persistence.jdbc.url" value="jdbc:mysql://myServer:3306/testdb?zeroDateTimeBehavior=convertToNull"/>
<property name="javax.persistence.jdbc.user" value="testdbuser"/>
<property name="javax.persistence.jdbc.driver" value="com.mysql.jdbc.Driver"/>
<property name="javax.persistence.jdbc.password" value="myPassword"/>
<property name="javax.persistence.schema-generation.database.action" value="create"/>
<!-- Weaving -->
<property name="eclipselink.weaving" value="static"/>
<!-- SQL dialect / Database type -->
<property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect"/>
<property name="eclipselink.target-database" value="MySQL"/>
<!-- Tell the JPA provider to, by default, create the table if it does not exist. -->
<property name="javax.persistence.schema-generation.database.action" value="create"/>
<!-- No logging (For development change the value to "FINE") -->
<property name="eclipselink.logging.level" value="OFF"/>
<!-- Enable batch writing -->
<property name="eclipselink.jdbc.batch-writing" value="JDBC"/>
<!-- Batch size -->
<property name="eclipselink.jdbc.batch-writing.size" value="500"/>
</properties>
</persistence-unit>
</persistence>
所以我的问题是,为什么它没有批量插入?我相信我已经从EclipseLink的网站和这里SO上阅读到的信息很好地配置了它。
////////////////////////////编辑//////////////////////////
如Chris的答案所建议的,在我的EntityClassTest中,我将这个值@GeneratedValue(strategy = GenerationType.IDENTITY)更改为@GeneratedValue(strategy = GenerationType.SEQUENCE),然后重新运行测试,数据包像我上面发布的图片一样被发送。所以恐怕它没有解决我的问题。
////////////////////////////编辑2//////////////////////////
我已经在persistence.xml文件中将日志级别更改为FINEST,如下所示。
<property name="eclipselink.logging.level" value="FINEST"/>
以下是您需要翻译的内容:
这是生成的日志记录。我将它放在Pastebin网站上,因为它非常长。
它似乎很多次调用了执行查询InsertObjectQuery
。
//////////////////////////// 编辑 3 ////////////////////////
这是我使用的每个组件的版本。
+-------------------------+------------------------------+
| Variable_name | Value |
+-------------------------+------------------------------+
| innodb_version | 5.6.12 |
| protocol_version | 10 |
| slave_type_conversions | |
| version | 5.6.12-log |
| version_comment | MySQL Community Server (GPL) |
| version_compile_machine | x86_64 |
| version_compile_os | Win64 |
+-------------------------+------------------------------+
Netbeans 8.0
EclipseLink (JPA 2.1)
mysql-connector-java-5.1.24.jar
//////////////////////////// 编辑 4 ////////////////////////
根据CuriousMind的回答,我编辑了我的EntityClassTest
id注解:
@Id
@GeneratedValue(strategy = GenerationType.AUTO, generator="id-seq-gen")
@SequenceGenerator( name="id-seq-gen", sequenceName="ID_SEQ_GEN", allocationSize=500 )
private Long id;
但它并没有解决我的问题,我仍然每个数据包只得到了一个插入(正如上面的图像所描述的那样),在EclipseLink
日志中,我得到了以下内容:
[EL Fine]: sql: 2014-10-19 06:44:02.608--ClientSession(824177287)--Connection(1674390738)--Thread(Thread[main,5,main])--SELECT LAST_INSERT_ID()
[EL Finest]: sequencing: 2014-10-19 06:44:02.608--UnitOfWork(1985011414)--Thread(Thread[main,5,main])--assign sequence to the object (1.251 -> database.EntityClassTest [id=null ])
[EL Finest]: query: 2014-10-19 06:44:02.608--UnitOfWork(1985011414)--Thread(Thread[main,5,main])--Execute query InsertObjectQuery(database.EntityClassTest [id=null ])
[EL Finest]: query: 2014-10-19 06:44:02.608--ClientSession(824177287)--Thread(Thread[main,5,main])--Execute query ValueReadQuery(name="ID_SEQ_GEN" sql="SELECT LAST_INSERT_ID()")
[EL Fine]: sql: 2014-10-19 06:44:02.608--ClientSession(824177287)--Connection(1674390738)--Thread(Thread[main,5,main])--INSERT INTO ENTITYCLASSTEST (LASTNAME, NAME) VALUES (?, ?)
bind => [sfirosijfhgdoi 2068, dsufius1034]
[EL Fine]: sql: 2014-10-19 06:44:02.608--ClientSession(824177287)--Connection(1674390738)--Thread(Thread[main,5,main])--SELECT LAST_INSERT_ID()
[EL Finest]: sequencing: 2014-10-19 06:44:02.608--UnitOfWork(1985011414)--Thread(Thread[main,5,main])--assign sequence to the object (1.252 -> database.EntityClassTest [id=null ])
[EL Finest]: query: 2014-10-19 06:44:02.608--UnitOfWork(1985011414)--Thread(Thread[main,5,main])--Execute query InsertObjectQuery(database.EntityClassTest [id=null ])
[EL Finest]: query: 2014-10-19 06:44:02.608--ClientSession(824177287)--Thread(Thread[main,5,main])--Execute query ValueReadQuery(name="ID_SEQ_GEN" sql="SELECT LAST_INSERT_ID()")
[EL Fine]: sql: 2014-10-19 06:44:02.608--ClientSession(824177287)--Connection(1674390738)--Thread(Thread[main,5,main])--INSERT INTO ENTITYCLASSTEST (LASTNAME, NAME) VALUES (?, ?)
bind => [sfirosijfhgdoi 2244, dsufius1122]
And so on...
persistence.xml
文件中的连接中添加rewriteBatchedStatements=true
。我已经在我的 JDBC 中添加了它,错误地认为我也在persistence.xml
中添加了它。这部分解决了我的问题。加上 Chris 的答案,问题完全解决了。 - dazito