在某些情况下,可能需要将一批记录插入到数据库中。如果你对每条记录调用一个插件的方法,SQL语句将被重复编译,造成系统缓慢进行。
在上述情况下,你可以使用 JdbcTemplate BATCHUPDATE()方法来执行批量插入操作。用这种方法,该语句只被编译一次,执行多次。
详见 JdbcTemplate 类的 BATCHUPDATE()示例。
//insert batch example public void insertBatch(final List<Customer> customers){ String sql = "INSERT INTO CUSTOMER " + "(CUST_ID, NAME, AGE) VALUES (?, ?, ?)"; getJdbcTemplate().batchUpdate(sql, new BatchPreparedStatementSetter() { @Override public void setValues(PreparedStatement ps, int i) throws SQLException { Customer customer = customers.get(i); ps.setLong(1, customer.getCustId()); ps.setString(2, customer.getName()); ps.setInt(3, customer.getAge() ); } @Override public int getBatchSize() { return customers.size(); } }); }
或者,可以直接执行SQL。
//insert batch example with SQL public void insertBatchSQL(final String sql){ getJdbcTemplate().batchUpdate(new String[]{sql}); }
Spring 的 bean 配置文件
<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd"> <bean id="customerDAO" class="com.yiibai.customer.dao.impl.JdbcCustomerDAO"> <property name="dataSource" ref="dataSource" /> </bean> <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource"> <property name="driverClassName" value="com.mysql.jdbc.Driver" /> <property name="url" value="jdbc:mysql://localhost:3306/yiibaijava" /> <property name="username" value="root" /> <property name="password" value="password" /> </bean> </beans>
执行它
package com.yiibai.common; import java.util.ArrayList; import java.util.List; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; import com.yiibai.customer.dao.CustomerDAO; import com.yiibai.customer.model.Customer; public class App { public static void main( String[] args ) { ApplicationContext context = new ClassPathXmlApplicationContext("Spring-Customer.xml"); CustomerDAO customerDAO = (CustomerDAO) context.getBean("customerDAO"); Customer customer1 = new Customer(1, "yiibai1",21); Customer customer3 = new Customer(2, "yiibai2",22); Customer customer2 = new Customer(3, "yiibai3",23); List<Customer>customers = new ArrayList<Customer>(); customers.add(customer1); customers.add(customer2); customers.add(customer3); customerDAO.insertBatch(customers); String sql = "UPDATE CUSTOMER SET NAME ='BATCHUPDATE'"; customerDAO.insertBatchSQL(sql); } }
在本例中,插入三条顾客的记录,并批量更新所有客户的名字。