query = session.createQuery("select new Student(s.name, s.age) from Student s"); List<Student> students = query.list(); for (Student stu : students) { System.out.println(stu.getName()); } ``` 这需要...
pagingSelect.append("SELECT * FROM (SELECT row_.*, ROWNUM AS rownum_ FROM ("); pagingSelect.append(sql); pagingSelect.append(") row_ WHERE ROWNUM ) WHERE rownum_ > ?"); return pagingSelect....
SELECT * FROM tbl_user; END; ``` 2. **创建新用户 - createUser** ```sql DROP PROCEDURE IF EXISTS `createUser`; CREATE PROCEDURE `createUser`(IN userid VARCHAR(50), IN name VARCHAR(50), IN blog ...
criteria.setProjection(Projections.sqlProjection("SELECT id, name FROM User", new String[]{"id", "name"}, new Type[]{LongType.INSTANCE, StringType.INSTANCE})); List[]> results = criteria.list(); ``...
User user = new User(); user.setName("张三"); user.setEmail("zhangsan@example.com"); session.save(user); tx.commit(); session.close(); ``` 2. **删(Delete)**: 删除操作对应于从数据库中移除一...
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String hql = "SELECT new com.example.CustomerSummary(c.name, SUM(ch.fee)) " + "FROM Customer c " + "JOIN c.charges ch " + "WHERE ch.chargeTimeBegin >= '2005-01-01' AND ch.chargeTimeEnd "GROUP BY ...
本文将详细讲解如何使用Hibernate来编写通用的数据库操作代码,包括插入(insert)、删除(delete)、更新(update)以及查询(select)方法。 1. 插入数据(insert) 插入数据的方法是通过调用`session.save()`...
return getHibernateTemplate().execute(new HibernateCallback() { public Object doInHibernate(Session session) throws HibernateException, SQLException { Connection conn = session.connection(); ...
String sql = "SELECT * FROM category WHERE id = ?"; try { Category category = (Category) queryRunner.query(sql, id, new BeanHandler(Category.class)); return category; } catch (SQLException e) { ...
例如,`select new User(usr.name, usr.age) from User usr where usr.age > 20`将创建一个新的User对象,其中包含查询结果的name和age属性。这要求User类有一个接受两个参数的构造函数。请注意,如果查询结果不包括...
String sql = "select * from user_manager t where t.user_id = " + userId; ``` 3. **获取 Connection**:通过 `Session` 的 `connection()` 方法获得数据库连接。 ```java Connection conn = session....
query = session.createQuery("select new Student(s.name, s.age) from Student s"); List<Student> students = query.list(); for (Student stu : students) { System.out.println(stu.getName()); } ``` 这需要...
这段代码的关键点在于使用了`select new`语法,这在Hibernate中是一种特殊的查询方式,允许开发者自定义返回结果的结构,而不是简单的返回实体对象。下面将详细解析这一用法以及其他相关的特殊查询技巧。 #### 三、...
pagingSelect.append("SELECT * FROM (SELECT row_.*, ROWNUM AS rownum_ FROM ("); pagingSelect.append(sql); pagingSelect.append(") row_ WHERE ROWNUM ) WHERE rownum_ > ?"); return pagingSelect....
SELECT * FROM tbl_user; END; ``` 2. **创建新用户 - createUser** ```sql DROP PROCEDURE IF EXISTS `createUser`; CREATE PROCEDURE `createUser`(IN userid VARCHAR(50), IN name VARCHAR(50), IN blog ...
criteria.setProjection(Projections.sqlProjection("SELECT id, name FROM User", new String[]{"id", "name"}, new Type[]{LongType.INSTANCE, StringType.INSTANCE})); List[]> results = criteria.list(); ``...
Student student = new Student(...); session.save(student); if (i % 50 == 0) { // 每50条记录提交一次 session.flush(); session.clear(); } } session.getTransaction().commit(); ``` #### 三、...
Configuration config = new Configuration().configure(); SessionFactory sessionFactory = config.buildSessionFactory(); ``` 五、查询数据表中的一个字段 1. HQL查询: HQL是一种面向对象的查询语言,类似于...
ResultSet resultSet = statement.executeQuery("SELECT content FROM media WHERE id = " + id); resultSet.next(); Blob blob = resultSet.getBlob("content"); InputStream blobInput = blob.getBinaryStream(); ...
SQLQuery query = session.createSQLQuery("SELECT * FROM users WHERE age > :age"); query.setParameter("age", 20); List[]> userRecords = query.list(); ``` 每种查询方式都有其适用场景,开发者可以根据...
当不与Spring框架结合使用时,Hibernate支持在HQL中直接使用中文字符进行模糊匹配,如`hql = "Select user From Userinfo user where user.username like '%用户名 5%'"`。但在Spring环境下,通常需要使用占位符`...
- `private static ThreadLocal<Session> sessionThreadLocal = new ThreadLocal();` - 在需要的地方获取当前线程的`Session`: - `Session session = sessionThreadLocal.get();` 以上就是关于Hibernate中HQL...
public List<Article> select(String pages, Map, Object> fromMap) { Session hibernateSession = HibernateSession.getSession(); // 获取数据库会话 PageController pageController = new PageController(); ...
User user = new User(); user.setName("张三"); user.setEmail("zhangsan@example.com"); session.save(user); tx.commit(); session.close(); ``` 2. **删(Delete)**: 删除操作对应于从数据库中移除一...