【发布时间】：2013-11-27 18:47:19
【问题描述】：
我正在尝试使用 JAP 和 HIBERNATE 将一些数据插入 SQL Server 2008 R2。一切都“有效”，除了它非常慢。插入 20000 行大约需要 45 秒，而 C# 脚本大约需要不到 1 秒。
该领域的任何资深人士都可以提供一些帮助吗？我将不胜感激。
更新：从下面的答案中得到了一些很好的建议，但它仍然无法按预期工作。速度是一样的。
这是更新后的 persistence.xml：
<persistence version="2.0"
xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd">
<persistence-unit name="ClusterPersist"
transaction-type="RESOURCE_LOCAL">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<class>cluster.data.persist.sqlserver.EventResult</class>
<exclude-unlisted-classes>true</exclude-unlisted-classes>
<properties>
<property name="javax.persistence.jdbc.url"
value="jdbc:sqlserver://MYSERVER:1433;databaseName=MYTABLE" />
<property name="javax.persistence.jdbc.user" value="USER" />
<property name="javax.persistence.jdbc.password" value="PASSWORD" />
<property name="javax.persistence.jdbc.driver"
value="com.microsoft.sqlserver.jdbc.SQLServerDriver" />
<property name="hibernate.show_sql" value="flase" />
<property name="hibernate.hbm2ddl.auto" value="update" />
<property name="hibernate.connection.provider_class"
value="org.hibernate.service.jdbc.connections.internal.C3P0ConnectionProvider" />
<property name="hibernate.c3p0.max_size" value="100" />
<property name="hibernate.c3p0.min_size" value="0" />
<property name="hibernate.c3p0.acquire_increment" value="1" />
<property name="hibernate.c3p0.idle_test_period" value="300" />
<property name="hibernate.c3p0.max_statements" value="0" />
<property name="hibernate.c3p0.timeout" value="100" />
<property name="hibernate.jdbc.batch_size" value="50" />
<property name="hibernate.cache.use_second_level_cache" value="false" />
</properties>
</persistence-unit>
这是更新的代码部分：
public static void writeToDB(String filePath) throws IOException {
EntityManager entityManager = entityManagerFactory.createEntityManager();
Session session = (Session) entityManager.getDelegate();
Transaction tx = session.beginTransaction();
int i = 0;
URL filePathUrl = null;
try {
filePathUrl = new URL(filePath);
} catch (MalformedURLException e) {
filePathUrl = (new File(filePath)).toURI().toURL();
}
String line = null;
BufferedReader stream = null;
try {
InputStream in = filePathUrl.openStream();
stream = new BufferedReader(new InputStreamReader(in));
// Read each line in the file
MyRow myRow = new MyRow();
while ((line = stream.readLine()) != null) {
String[] splitted = line.split(",");
int num1 = Integer.valueOf(splitted[1]);
float num2= Float.valueOf(splitted[6]).intValue();
myRow.setNum1(num1);
myRow.setNum2(num2);
session.save(myRow);
if (i % 50 == 0) {
session.flush();
session.clear();
}
i++;
}
tx.commit();
} finally {
if (stream != null)
stream.close();
}
session.close();
}
已更新，这是 MyRow 的来源：
@Entity
@Table(name="MYTABLE")
public class MyRow {
@Id
@GeneratedValue(strategy=GenerationType.IDENTITY)
private Long id;
@Basic
@Column(name = "Num1")
private int Num1;
@Basic
@Column(name = "Num2")
private float Num2;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public float getNum1() {
return Num1;
}
public void setNum1(float num1) {
Num1 = num1;
}
public int getNum2() {
return Num2;
}
public void setNum2(int num2) {
Num2 = num2;
}
}
【问题讨论】：
标签： sql sql-server database hibernate jpa