hql大全

package xy.Test;

import java.util.Date;
import java.util.List;

import org.hibernate.Query;
import org.hibernate.SQLQuery;
import org.hibernate.Session;
import org.hibernate.cfg.AnnotationConfiguration;
import org.hibernate.tool.hbm2ddl.SchemaExport;

import xy.Utility.HibernateAnnotationUtil;
import xy.model.Category;
import xy.model.Msg;
import xy.model.Topic;

public class TestClass
{

public static void Insert()
{
Session session = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
session.beginTransaction();

// 设置10个板块
for(int i = 0;i<10;i++)
{
Category c = new Category();
c.setName("c" + i);
session.save(c);
}

// 给第一个板块设置10个主题
for(int i = 0;i<10;i++)
{
Category c = (Category)session.get(Category.class, 1);
Topic t = new Topic();
t.setCategory(c);
t.setTitle("t" + i);
t.setCreateTime(new Date());
session.save(t);
}

// 给第一个板块设置10条回复
for(int i = 0;i<10;i++)
{
Topic t = (Topic)session.get(Topic.class, 1);
Msg m = new Msg();
m.setContent("m"+i);
m.setTopic(t);
session.save(m);
}
session.getTransaction().commit();
}

public static void GetList()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select c from Category c");
List<Category> list = (List<Category>)q.list();
for(Category c : list)
{
System.out.println(c.getName());
}
s.getTransaction().commit();
}


public static void GetList1()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select c from Category c where c.name > 'c5'");
List<Category> list = (List<Category>)q.list();
for(Category c : list)
{
System.out.println(c.getName());
}
s.getTransaction().commit();
}

public static void GetOrderedList()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select c from Category c order by c.name desc");
List<Category> list = (List<Category>)q.list();
for(Category c : list)
{
System.out.println(c.getName());
}
s.getTransaction().commit();
}

public static void GetOrderedList2()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select distinct c from Category c order by c.name desc");
List<Category> list = (List<Category>)q.list();
for(Category c : list)
{
System.out.println(c.getName());
}
s.getTransaction().commit();
}

public static void GetOrderedList3()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select c from Category c where c.id > :min and c.id< :max");
//q.setParameter("min", 2);
//q.setParameter("max", 8);
q.setInteger("min", 2);
q.setInteger("max", 8);
List<Category> list = (List<Category>)q.list();
for(Category c : list)
{
System.out.println(c.getName());
}
s.getTransaction().commit();
}

// 可以用于分页
public static void GetOrderedListPage()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select c from Category c");
q.setMaxResults(5);
q.setFirstResult(2);
List<Category> list = (List<Category>)q.list();
for(Category c : list)
{
System.out.println(c.getName());
}
s.getTransaction().commit();
}

public static void GetNameList()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select c.name from Category c");
List<String> list = (List<String>)q.list();
for(String str : list)
{
System.out.println(str);
}
s.getTransaction().commit();
}

public static void GetIdAndNameList()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select c.id, c.name from Category c");
List<Object[]> list = (List<Object[]>)q.list();
for(Object[] o : list)
{
System.out.println(o[0] + "........" + o[1]);
}
s.getTransaction().commit();
}

// 体现了对象之间的关联
public static void GetTopic()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select t.title from Topic t where t.category.id = 1");
List<String> list = (List<String>)q.list();
for(String str : list)
{
System.out.println(str);
}
s.getTransaction().commit();
}


// 体现了对象之间的关联
public static void GetMsg()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select m from Msg m where m.topic.category.id = 1");
List<Msg> list = (List<Msg>)q.list();
for(Msg m : list)
{
System.out.println(m.getContent());
}
s.getTransaction().commit();
}

public static void Join()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select c.name,t.title from Topic t join t.category c");
List<Object[]> list = (List<Object[]>)q.list();
for(Object[] m : list)
{
System.out.println(m[0]+ "...."+m[1]);
}
s.getTransaction().commit();
}


public static void UniqueResult()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select m from Msg m where m = :MsgResult");
Msg m = new Msg();
m.setId(1);
q.setParameter("MsgResult", m);

// 会使用UniqueResult
Msg msg = (Msg)q.uniqueResult();
System.out.println(msg.getContent());
s.getTransaction().commit();

}

public static void GetCount()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select count(*) from Msg");
long count = (Long)q.uniqueResult();
System.out.println(count);
}

public static void MinOrMaxList()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select max(m.id),min(m.id),avg(m.id),sum(m.id) from Msg m");
Object[] o = (Object[])q.uniqueResult();
System.out.println(o[0] + "-" + o[1] + "-" + o[2] + "-" + o[3]);
}


public static void BetweenList()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select m from Msg m where m.id between 3 and 5");

List<Msg> list = (List<Msg>)q.list();
for(Msg m : list)
{
System.out.println(m.getContent());
}
s.getTransaction().commit();
}

public static void InList()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select m from Msg m where m.id in (3,4,5)");

List<Msg> list = (List<Msg>)q.list();
for(Msg m : list)
{
System.out.println(m.getContent());
}
s.getTransaction().commit();
}

public static void IsNotNull()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select m from Msg m where m.content is not null");

List<Msg> list = (List<Msg>)q.list();
for(Msg m : list)
{
System.out.println(m.getContent());
}
s.getTransaction().commit();
}

// is not empty针对集合
public static void IsNotEmpty()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select t from Topic t where t.listMsg is not empty");

List<Topic> list = (List<Topic>)q.list();
for(Topic m : list)
{
System.out.println(m.getId());
}
s.getTransaction().commit();
}

// %表示多个匹配
// _表示一个匹配
public static void Like1()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select t from Topic t where t.title like '%5'");

List<Topic> list = (List<Topic>)q.list();
for(Topic m : list)
{
System.out.println(m.getId());
}
s.getTransaction().commit();
}


public static void Like2()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select t from Topic t where t.title like '_5'");

List<Topic> list = (List<Topic>)q.list();
for(Topic m : list)
{
System.out.println(m.getId());
}
s.getTransaction().commit();
}

public static void SomeMethods()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select lower(t.title),"
+"upper(t.title),"
+"trim(t.title),"
+"concat(t.title,'***'),"
+"length(t.title)"
+" from Topic t");

List<Object[]> list = (List<Object[]>)q.list();
for(Object[] m : list)
{
System.out.println(m[0] + "...." + m[1] + "....." +m[3]);
}
s.getTransaction().commit();
}

// 取数据库服务器时间
// 为什么要取数据库时间呢？因为可能多台服务器围绕一个数据库服务器
public static void DateMethods()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select current_date,current_time,current_timestamp,t.id from Topic t");

List<Object[]> list = (List<Object[]>)q.list();
for(Object[] m : list)
{
System.out.println(m[0] + "...." + m[1] + "....." +m[2] + "......." + m[3]);
}
s.getTransaction().commit();
}


// 取数据库服务器时间
// 为什么要取数据库时间呢？因为可能多台服务器围绕一个数据库服务器
public static void DateMethods2()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select t.id,t.title from Topic t where t.createTime <= :Date");
q.setParameter("Date", new Date());

List<Object[]> list = (List<Object[]>)q.list();
for(Object[] m : list)
{
System.out.println(m[0] + "...." + m[1]);
}
s.getTransaction().commit();
}

// Group by 后面必须出现在select里面
public static void GroupBy()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select t.title,count(*) from Topic t group by t.title");

List<Object[]> list = (List<Object[]>)q.list();
for(Object[] m : list)
{
System.out.println(m[0] + "...." + m[1]);
}
s.getTransaction().commit();
}

// having后面跟的是函数，否则的话用where就行了
public static void HavingMehtods()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select t.title,count(*) from Topic t group by t.title having count(*) >= 1");

List<Object[]> list = (List<Object[]>)q.list();
for(Object[] m : list)
{
System.out.println(m[0] + "...." + m[1]);
}
s.getTransaction().commit();
}

// 查询语句嵌套
public static void Embedded()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select t.title,t.id from Topic t where t.id < (select avg(t.id) from Topic t)");

List<Object[]> list = (List<Object[]>)q.list();
for(Object[] m : list)
{
System.out.println(m[0] + "...." + m[1]);
}
s.getTransaction().commit();
}


// All指的是取到的所有值
// < All指的是小于取到的所有值，也就是取最小的值
public static void AllMethods()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select t.title,t.id from Topic t where t.id < ALL(select t.id from Topic t)");

List<Object[]> list = (List<Object[]>)q.list();
for(Object[] m : list)
{
System.out.println(m[0] + "...." + m[1]);
}
s.getTransaction().commit();
}

// exsit方法的用法
// 查找没有回复的主题
// 与IsNotEmpty()效果一样
// exists比in效率高
public static void ExistOrNot()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select t.title,t.id from Topic t where not exists (select m.id from Msg m where m.topic.id = t.id)");
List<Object[]> list = (List<Object[]>)q.list();
for(Object[] m : list)
{
System.out.println(m[0] + "...." + m[1]);
}
s.getTransaction().commit();
}


public static void Update()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("update Topic t set t.title = upper(t.title)");
q.executeUpdate();
s.getTransaction().commit();
}


public static void Delete()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("delete Msg m where m.id = 1");
q.executeUpdate();
s.getTransaction().commit();
}

public static void GetQueryWithQueryName()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
Query q = s.getNamedQuery("select.certainTopic");
q.setParameter("id", 5);
Topic t = (Topic)q.uniqueResult();
System.out.println(t.getTitle());
s.getTransaction().commit();
}

// NativeSQL
// 这里from的是表名，不是对象名
public static void NativeSQL()
{
Session s = HibernateAnnotationUtil.getSessionFactory().getCurrentSession();
s.beginTransaction();
SQLQuery q = s.createSQLQuery("select * from category limit 2,5").addEntity(Category.class);
List<Category> list = (List<Category>)q.list();
for(Category c : list)
{
System.out.println(c.getName());
}

s.getTransaction().commit();
}

}