Hibernate5.2之原生SQL查询

来源:互联网 发布:如何卸载mysql 编辑:程序博客网 时间:2024/06/03 09:38

原文:http://www.cnblogs.com/miller-zou/p/5720048.html

一. 介绍

   在上一篇博客中笔者通过代码的形式给各位读者介绍了Hibernate中最重要的检索方式--HQL查询。在本博文中笔者将向各位读者介绍Hibernate中的原生SQL查询,虽为原生SQL查询,但是笔者认为Hibernate在针对不同的数据库在分页语句的处理上做的很不错,我们不用去关心使用的是何种的数据库。本博文会沿用《Hibernate5.2之HQL查询》中的POJO类和配置文件,请各位看官在阅读本博文之前请先阅读该文章,本篇文章会将HQL中涉及的相关操作原封不动的全部改为SQL查询,所以在代码上的重复度比较的高,请各位读者勿喷,那我们就直接上单元测试了。

二. 单元测试

A.获取所有的Order对象,得到一个List集合

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@Testpublic void list(){    String sql = "select * from orders";    NativeQuery<Order> query = session.createNativeQuery(sql, Order.class);    List<Order> list = query.getResultList();    for(Order o : list){         System.out.println(o.getId() + "::" + o.getOrderId());    }}
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B.获取Order的分页数据,得到一个List集合

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/** * 虽然为原生的SQL查询,但是依然可以使用setFirstResult()和setMaxResults()方法。从而屏蔽了 * 底层数据库的差异性。 */@Testpublic void pageList(){    String sql = "select * from orders";    //setFirstResult()从0开始    Query<Order> query = session.createNativeQuery(sql, Order.class).setFirstResult(1).setMaxResults(4);    List<Order> list = query.getResultList();    for(Order o : list){         System.out.println(o.getId());    }}
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C.多条件查询,返回List集合(第一种形式:索引占位符)

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@Testpublic void multiCretiera(){    String sql = "select * from orders where create_time between ? and ? and order_id like ?";    Query<Order> query = session.createNativeQuery(sql, Order.class);    String beginDateStr = "2016-07-26 00:00:00";    String endDateStr = "2016-07-28 23:59:59";    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");    Date beginDate = null;    Date endDate = null;    try {         beginDate = sdf.parse(beginDateStr);         endDate = sdf.parse(endDateStr);    } catch (ParseException e) {         e.printStackTrace();    }    //分页从0开始    query.setParameter(0, beginDate).setParameter(1, endDate).setParameter(2, "%D%").setFirstResult(0).setMaxResults(1);    List<Order> list = query.getResultList();    for(Order o : list){         System.out.println(o.getOrderId() + "::" + o.getCreateTime());    }}
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D.多条件查询,返回List集合(第二种形式:命名占位符)

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@Testpublic void multiCretiera1(){    String sql = "select * from orders where order_id like :orderId and create_time between :beginDate and :endDate";    Query<Order> query = session.createNativeQuery(sql, Order.class);    String beginDateStr = "2016-07-26 00:00:00";    String endDateStr = "2016-07-28 23:59:59";    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");    Date beginDate = null;    Date endDate = null;    try {         beginDate = sdf.parse(beginDateStr);         endDate = sdf.parse(endDateStr);    } catch (ParseException e) {         e.printStackTrace();    }    query.setParameter("orderId", "%D%").setParameter("beginDate", beginDate).setParameter("endDate", endDate);    List<Order> list = query.getResultList();    for(Order o : list){         System.out.println(o.getId() + "::" + o.getOrderId());    }}
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E.大于条件的查询,使用索引占位符

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@Testpublic void gt(){    String sql = "select * from orders where id > ?";    Query<Order> query = session.createNativeQuery(sql, Order.class).setParameter(0, 3);    List<Order> list = query.getResultList();    for(Order o : list){        System.out.println(o.getId() + "::" + o.getOrderId());    }}
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F.删除操作

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@Testpublic void delete(){    String sql = "delete from orders where id in (:idList)";     Transaction tx = session.beginTransaction();    List<Integer> list = new ArrayList<Integer>();    list.add(1);    list.add(2);    Query<?> query = session.createNativeQuery(sql).setParameter("idList", list);    int i = query.executeUpdate();    System.out.println(i);    tx.commit();    session.close();}
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G.获取某一列的值

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@Testpublic void singleValue(){    String sql = "select order_id from orders";    Query<String> query = session.createNativeQuery(sql);    List<String> list = query.getResultList();    for(String str : list){        System.out.println(str);    }}
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 H.获取关联对象的结果集

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@Testpublic void getCustomer(){    String sql = "select c.* from orders o join customer c on o.customer_id = c.id where c.id = 8";    Query<Customer> query = session.createNativeQuery(sql, Customer.class);    List<Customer> list = query.getResultList();    for(Customer o : list){        System.out.println(o.getId() + ";;");    }}
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 I.多列数据的查询

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@Testpublic void getObjectArray(){    String sql = "select c.name, c.phone_number, o.order_id, o.create_time from orders o join customer c on o.customer_id = c.id";    Query<Object[]> query = session.createNativeQuery(sql);    List<Object[]> list = query.getResultList();    for(Object[] o : list){         System.out.println(o[0] + ";;" + o[1] + ";;" + o[2]);    }}
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J.函数查询

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@Testpublic void functionQuery(){    String sql = "select max(id), count(*) from orders";    Query<Object[]> query = session.createNativeQuery(sql);    Object[] obj = query.getSingleResult();    System.out.println(obj[0] + "::" + obj[1]);}
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 K.排序

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@Testpublic void descQuery(){    String sql = "select * from orders order by id desc";    Query<Order> query = session.createNativeQuery(sql, Order.class);    List<Order> list = query.getResultList();    for(Order o : list){        System.out.println(o.getId() + "::" + o.getOrderId());    }}
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L.右连接

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@Testpublic void rightJoin(){    String sql = "select c.* from orders o right join customer c on o.customer_id = c.id";    Query<Customer> query = session.createNativeQuery(sql, Customer.class);    List<Customer> list = query.getResultList();    for(Customer c : list){        System.out.println(c.getId());    }}
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