hibernate HQL查询
先来个结构图吧
这里是代码 :
private Configuration config;
private SessionFactory sessionFactory;
private Session session;
private Transaction transaction;
public void after() {
transaction.commit();
session.close();
sessionFactory.close();
}
public void defore() {
config = new Configuration().configure();
sessionFactory = config.buildSessionFactory();
session = sessionFactory.openSession();
transaction = session.beginTransaction();
}
/**
* 查询所有
*/
@Test
public void getAll() {
List<T_user> lt = session.createQuery("from T_user ").list();
System.out.println(lt.size());
System.out.println(JSON.toJSON(lt));
}
/**
* 查询某咧
*/
@Test
public void getAll1() {
List<T_user> lt = session.createQuery("select user_id from T_user").list();
System.out.println(lt.size());
System.out.println(JSON.toJSON(lt));
}
/**
* 查询某几列
*/
@Test
public void getAll2() {
List<T_user> lt = session.createQuery("select user_id,user_name from
T_user").list();
System.out.println(lt.size());
System.out.println(JSON.toJSON(lt));
}
/**
* 构造查询
*/
@Test
public void getAll3() {
List<T_user> lt = session.createQuery(" select new t_user (user_id,user_name)
from t_user").list();
System.out.println(JSON.toJSON(lt));
}
/**
* 条件查询
*/
@Test
public void getAll4() {
List<T_user> lt = session.createQuery("from T_user where user_id=?").list();
System.out.println(JSON.toJSON(lt));
}
/**
* 聚合函数
*/
@Test
public void getAll5() {
List<T_user> lt = session.createQuery("select count(user_id) from
T_user").list();
System.out.println(JSON.toJSON(lt));
}
/**
* 分页
*/
@Test
public void getAll6() {
List<T_user> lt = session.createQuery(" from
T_user").setFirstResult(1).setMaxResults(5).list();
System.out.println(JSON.toJSON(lt));
}
/**
* like
*/
public void getAll7() {
List<T_user> lt = session.createQuery("from User where name
like:user_name").setString(("user_name"), "%123%")
.list();
System.out.println(JSON.toJSON(lt));
}
/**
* 排序
*/
public void getAll8() {
List<T_user> lt = session.createQuery(" from T_user order asc").list();
System.out.println(JSON.toJSON(lt));
}
/**
* 修改
*/
public void edit() {
int lt = session.createQuery(" update T_user set
user_name=7777").executeUpdate();
System.out.println(lt);
}
/**
* 删除
*/
public void ro() {
int l = session.createQuery("delete T_user where user_id=1").executeUpdate();
System.out.println(l);
}