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Hibernate5

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HQL

基本查询

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package me.yanrs.service;

import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;

import me.yanrs.utils.HibernateUtils;

public class HQL_Day4 {
	public static void main(String[] args) {
		basic_hql();
	}

	private static void basic_hql() {
		Session session = HibernateUtils.getCurrentSession();
		Transaction tx = session.beginTransaction();
		
		String hql1 = "from User";    //简单写法
		String hql2 = "from me.yanrs.domain.User";    //完整写法
		String hql3 = "from java.lang.Object";		//查询到
		
		Query createQuery = session.createQuery(hql1);
		System.out.println(createQuery.list());
		
		Query createQuery2 = session.createQuery(hql2);
		System.out.println(createQuery2.list());
		
		Query createQuery3 = session.createQuery(hql3);
		System.out.println(createQuery3.list());
		
		tx.commit();
	}
}

排序

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package me.yanrs.service;

import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;

import me.yanrs.utils.HibernateUtils;

public class HQL_Day4 {
	public static void main(String[] args) {
		//basic_hql();
		orderby_hql();
	}

	private static void orderby_hql() {
		Session session = HibernateUtils.getCurrentSession();
		Transaction tx = session.beginTransaction();
		
		String hql = "from me.yanrs.domain.User order by user_id asc";
		String hql2 = "from me.yanrs.domain.User order by user_id desc";
		
		Query query = session.createQuery(hql);
		Query query2 = session.createQuery(hql2);
		
		System.out.println(query.list());
		System.out.println(query2.list());
		
		tx.commit();
	}
}

条件

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package me.yanrs.service;

import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.annotations.Where;

import me.yanrs.utils.HibernateUtils;

public class HQL_Day4 {
	public static void main(String[] args) {
		//basic_hql();
		//orderby_hql();
		Where_hql();
	}

	private static void Where_hql() {
		Session session = HibernateUtils.getCurrentSession();
		Transaction tx = session.beginTransaction();
		
		String hql = "from me.yanrs.domain.User where user_id=?";
		String hsql2 = "from me.yanrs.domain.User where user_id=:id";
		
		Query query = session.createQuery(hql);
		Query query2 = session.createQuery(hsql2);
		
		query.setParameter(0, 1l);
		query2.setParameter("id", 1l);
		
		System.out.println(query.list());
		System.out.println(query2.list());
		
		tx.commit();
	}
}

分页

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package me.yanrs.service;

import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.annotations.Where;

import me.yanrs.utils.HibernateUtils;

public class HQL_Day4 {
	public static void main(String[] args) {
		//basic_hql();
		//orderby_hql();
		//Where_hql();
		fenye_hql();
	}

	private static void fenye_hql() {
		Session session = HibernateUtils.getCurrentSession();
		Transaction transaction = session.beginTransaction();
		
		String hql = "from me.yanrs.domain.User";
		Query query = session.createQuery(hql);
		
		query.setFirstResult(0);
		query.setMaxResults(5);
		
		System.out.println(query.list());
		transaction.commit();
	}
}

聚合

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package me.yanrs.service;

import org.hibernate.Query;
import org.hibernate.SQLQuery;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.annotations.Where;

import me.yanrs.utils.HibernateUtils;

public class HQL_Day4 {
	public static void main(String[] args) {
		//basic_hql();
		//orderby_hql();
		//Where_hql();
		//fenye_hql();
		hql_count();
	}

	private static void hql_count() {
		//count	计数
		//sum 	求和
		//avg	平均数
		//max   最大值
		//min   最小值
		
		Session session = HibernateUtils.getCurrentSession();
		Transaction transaction = session.beginTransaction();
		
		String hql = "select count(*) from me.yanrs.domain.User";
		String hql2 = "select sum(user_id) from me.yanrs.domain.User";
		String hql3 = "select avg(user_id) from me.yanrs.domain.User";
		String hql4 = "select max(user_id) from me.yanrs.domain.User";
		String hql5 = "select min(user_id) from me.yanrs.domain.User";
		
		Query query = session.createQuery(hql);
		Query query2 = session.createQuery(hql2);
		Query query3 = session.createQuery(hql3);
		Query query4 = session.createQuery(hql4);
		Query query5 = session.createQuery(hql5);
		
		System.out.println(query.uniqueResult());
		System.out.println(query2.uniqueResult());
		System.out.println(query3.uniqueResult());
		System.out.println(query4.uniqueResult());
		System.out.println(query5.uniqueResult());
		
		transaction.commit();
	}
}

字段查询

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package me.yanrs.service;

import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;

import me.yanrs.utils.HibernateUtils;

public class HQL_Day4 {
	public static void main(String[] args) {
		//basic_hql();
		//orderby_hql();
		//Where_hql();
		//fenye_hql();
		//hql_count();
		hql_field_select();
	}

	private static void hql_field_select() {
		Session session = HibernateUtils.getCurrentSession();
		Transaction transaction = session.beginTransaction();
		
		String hql = "select user_id, user_name from me.yanrs.domain.User";
		String hql2 = "select  new User(user_id,user_name) from me.yanrs.domain.User";  //使用这个的时候实体类要有构造方法，且构造方法的参数和这个要一样
		
		Query query = session.createQuery(hql);
		Query query2 = session.createQuery(hql2);
		
		System.out.println(query.list());
		System.out.println(query2.list());
		
		transaction.commit();
	}
}

内连接

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package me.yanrs.service;
import java.util.Arrays;
import java.util.List;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;
import me.yanrs.utils.HibernateUtils;

public class HQL_Day4 {
	public static void main(String[] args) {
		//basic_hql();
		//orderby_hql();
		//Where_hql();
		//fenye_hql();
		//hql_count();
		//hql_field_select();
		//inner_join();
	}

	private static void inner_join() {
		Session session = HibernateUtils.getCurrentSession();
		Transaction transaction = session.beginTransaction();
		String hql = "from User u inner join u.roles";
		Query query = session.createQuery(hql);
		List<Object[]> list = query.list();
		
		for (Object[] arr : list) {
			System.out.println(Arrays.toString(arr));
		}
		transaction.commit();
	}
}

迫切内连接

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package me.yanrs.service;
import java.util.Arrays;
import java.util.List;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;
import me.yanrs.utils.HibernateUtils;

public class HQL_Day4 {
	public static void main(String[] args) {
		//basic_hql();
		//orderby_hql();
		//Where_hql();
		//fenye_hql();
		//hql_count();
		//hql_field_select();
		//inner_join();
		inner_join_fetch();
	}
	
	private static void inner_join_fetch() {
		Session session = HibernateUtils.getCurrentSession();
		Transaction transaction = session.beginTransaction();
		String hql = "from User u inner join fetch u.roles";
		Query query = session.createQuery(hql);
		System.out.println(query.list());
		transaction.commit();
	}
}

区别：使用内连接返回list中每部分是数组，迫切内连接返回list每部分是对象

左外连接

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package me.yanrs.service;
import java.util.Arrays;
import java.util.List;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;
import me.yanrs.utils.HibernateUtils;

public class HQL_Day4 {
	public static void main(String[] args) {
		//basic_hql();
		//orderby_hql();
		//Where_hql();
		//fenye_hql();
		//hql_count();
		//hql_field_select();
		//inner_join();
		//inner_join_fetch();
		left_join();
	}
	
	private static void left_join() {
		Session session = HibernateUtils.getCurrentSession();
		Transaction tx = session.beginTransaction();
		String hql = "from User u left join u.roles";
		Query query = session.createQuery(hql);
		System.out.println(query.list());
		tx.commit();
	}
}

右外连接

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package me.yanrs.service;
import java.util.Arrays;
import java.util.List;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;
import me.yanrs.utils.HibernateUtils;

public class HQL_Day4 {
	public static void main(String[] args) {
		//basic_hql();
		//orderby_hql();
		//Where_hql();
		//fenye_hql();
		//hql_count();
		//hql_field_select();
		//inner_join();
		//inner_join_fetch();
		//left_join();
		right_join();
	}
	
	private static void right_join() {
		Session session = HibernateUtils.getCurrentSession();
		Transaction tx = session.beginTransaction();
		String hql = "from User u right join u.roles";
		Query query = session.createQuery(hql);
		System.out.println(query.list());
		tx.commit();
	}
}

Criteria

基本语法

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package me.yanrs.service;

import org.hibernate.Criteria;
import org.hibernate.Session;
import org.hibernate.Transaction;

import me.yanrs.domain.User;
import me.yanrs.utils.HibernateUtils;

public class Criteria_Day4 {
	public static void main(String[] args) {
		bacic_select();
	}

	private static void bacic_select() {
		Session session = HibernateUtils.getCurrentSession();
		Transaction transaction = session.beginTransaction();
		Criteria criteria = session.createCriteria(User.class);
		
		System.out.println(criteria.list());
		transaction.commit();
	}
}

条件查询

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package me.yanrs.service;

import org.hibernate.Criteria;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.criterion.Restrictions;

import me.yanrs.domain.User;
import me.yanrs.utils.HibernateUtils;

public class Criteria_Day4 {
	public static void main(String[] args) {
		//bacic_select();
		Where_select();
	}

	private static void Where_select() {
		Session session = HibernateUtils.getCurrentSession();
		Transaction transaction = session.beginTransaction();
		
		Criteria criteria = session.createCriteria(User.class);
		criteria.add(Restrictions.idEq(1l));
		
		System.out.println(criteria.list());
		transaction.commit();
	}
}

分页查询

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package me.yanrs.service;
import org.hibernate.Criteria;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.criterion.Restrictions;
import me.yanrs.domain.User;
import me.yanrs.utils.HibernateUtils;

public class Criteria_Day4 {
	public static void main(String[] args) {
		//bacic_select();
		//Where_select();
		fenye();
	}

	private static void fenye() {
		Session session = HibernateUtils.getCurrentSession();
		Transaction tx = session.beginTransaction();
		
		Criteria criteria = session.createCriteria(User.class);
		criteria.setFirstResult(0);
		criteria.setMaxResults(5);
		System.out.println(criteria.list());
		
		tx.commit();
	}
}

排序查询

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package me.yanrs.service;
import org.hibernate.Criteria;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.criterion.Order;
import org.hibernate.criterion.Restrictions;
import me.yanrs.domain.User;
import me.yanrs.utils.HibernateUtils;

public class Criteria_Day4 {
	public static void main(String[] args) {
		//bacic_select();
		//Where_select();
		//fenye();
		order_select();
	}

	private static void order_select() {
		Session session = HibernateUtils.getCurrentSession();
		Transaction transaction = session.beginTransaction();
		
		Criteria criteria = session.createCriteria(User.class);
		criteria.addOrder(Order.asc("user_id"));
		
		System.out.println(criteria.list());
		transaction.commit();
	}
}

聚合查询

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package me.yanrs.service;
import org.hibernate.Criteria;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.criterion.Order;
import org.hibernate.criterion.Projection;
import org.hibernate.criterion.Projections;
import org.hibernate.criterion.Restrictions;
import me.yanrs.domain.User;
import me.yanrs.utils.HibernateUtils;

public class Criteria_Day4 {
	public static void main(String[] args) {
		//bacic_select();
		//Where_select();
		//fenye();
		//order_select();
		select_count();
	}

	private static void select_count() {
		Session session = HibernateUtils.getCurrentSession();
		Transaction tx = session.beginTransaction();
		
		Criteria criteria = session.createCriteria(User.class);
		//criteria.setProjection(Projections.rowCount());
		//criteria.setProjection(Projections.max("user_id"));
		//criteria.setProjection(Projections.min("user_id"));
		criteria.setProjection(Projections.avg("user_id"));
		
		System.out.println(criteria.uniqueResult());
		tx.commit();
	}
}

离线查询

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package me.yanrs.service;
import org.hibernate.Criteria;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.criterion.DetachedCriteria;
import org.hibernate.criterion.Order;
import org.hibernate.criterion.Projection;
import org.hibernate.criterion.Projections;
import org.hibernate.criterion.Restrictions;
import me.yanrs.domain.User;
import me.yanrs.utils.HibernateUtils;

public class Criteria_Day4 {
	public static void main(String[] args) {
		//bacic_select();
		//Where_select();
		//fenye();
		//order_select();
		//select_count();
		detached();
	}

	private static void detached() {
		// 模拟web层或者service层
		
		DetachedCriteria detachedCriteria = DetachedCriteria.forClass(User.class);
		detachedCriteria.add(Restrictions.idEq(1l));
		
		//模拟dao层
		Session session = HibernateUtils.getCurrentSession();
		Transaction transaction = session.beginTransaction();
		Criteria criteria = detachedCriteria.getExecutableCriteria(session);
		
		System.out.println(criteria.list());
		transaction.commit();
	}
}