如何有效地在表中插入约500.000个数据行

Question

我有大约500.000行数据要插入到一个表中.

我目前正在插入一个(我知道它很糟糕),如下所示:

道法:

public static final String SET_DATA = "insert into TABLE (D_ID, N_ID, VALUE, RUN_ID) " + "values (?, ?, ?, ?)";

public void setData(String dId, String nId, BigDecimal value, Run run) throws HibernateException {
    if (session == null) {
        session = sessionFactory.openSession();
    }

    SQLQuery select = session.createSQLQuery(SET_DATA);
    select.setString(0, dId);
    select.setString(1, nId);
    select.setBigDecimal(2, value);
    select.setLong(3, run.getRunId());

    select.executeUpdate();
}

我怎样才能更有效地做到这一点？

Answer 1

为什么你去手写SQL查询？如果你以这种方式编写sql,你肯定无法获得休眠的成果.

学习Batch Insert示例代码Batch Insert,

    Session session = sessionFactory.openSession();
Transaction tx = session.beginTransaction();

for ( int i=0; i<100000; i++ ) {
    Customer customer = new Customer(.....);
    session.save(customer);
    if ( i % 20 == 0 ) { //20, same as the JDBC batch size
        //flush a batch of inserts and release memory:
        session.flush();
        session.clear();
    }
}

tx.commit();
session.close();