01.環(huán)境搭建

02.基本查詢

1.方法說明

方法	說明
Restrictions.eq	＝
Restrictions.allEq	利用Map來進(jìn)行多個等于的限制
Restrictions.gt	＞
Restrictions.ge	＞＝
Restrictions.lt	＜
Restrictions.le	＜＝
Restrictions.between	BETWEEN
Restrictions.like	LIKE
Restrictions.in	in
Restrictions.and	and
Restrictions.or	or
Restrictions.sqlRestriction	用SQL限定查詢

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2，QBC常用限定方法

Restrictions.eq?--> equal,等于.

Restrictions.allEq?--> 參數(shù)為Map對象,使用key/value進(jìn)行多個等于的比對,相當(dāng)于多個Restrictions.eq的效果

Restrictions.gt?--> great-than > 大于

Restrictions.ge?--> great-equal >= 大于等于

Restrictions.lt?--> less-than, < 小于

Restrictions.le?--> less-equal <= 小于等于

Restrictions.between?--> 對應(yīng)SQL的between子句

Restrictions.like?--> 對應(yīng)SQL的LIKE子句

Restrictions.in?--> 對應(yīng)SQL的in子句

Restrictions.and?--> and 關(guān)系

Restrictions.or?--> or 關(guān)系

Restrictions.isNull?--> 判斷屬性是否為空,為空則返回true

Restrictions.isNotNull?--> 與isNull相反

Restrictions.sqlRestriction?--> SQL限定的查詢

Order.asc?--> 根據(jù)傳入的字段進(jìn)行升序排序

Order.desc?--> 根據(jù)傳入的字段進(jìn)行降序排序

MatchMode.EXACT?--> 字符串精確匹配.相當(dāng)于"like 'value'"

MatchMode.ANYWHERE?--> 字符串在中間匹配.相當(dāng)于"like '%value%'"

MatchMode.START?--> 字符串在最前面的位置.相當(dāng)于"like 'value%'"

MatchMode.END?--> 字符串在最后面的位置.相當(dāng)于"like '%value'"

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01.基本操作

package com.gordon.test;import java.util.List;import org.hibernate.Criteria; import org.hibernate.Session; import org.hibernate.Transaction; import org.hibernate.criterion.Order; import org.hibernate.criterion.Restrictions; import org.junit.Test;import com.gordon.domain.Book; import com.gordon.utils.HibernateUtil;/*** QBC查詢* @author Administrator**/ public class TestQBCDemo1 {/*** 基本查詢*/@Testpublic void run1() {Session session = HibernateUtil.getCurrentSession();Transaction transaction = session.beginTransaction();// 穿件criteria查詢接口Criteria query = session.createCriteria(Book.class);query.addOrder(Order.asc("price"));query.add(Restrictions.le("price", 40.00));List<Book> list = query.list();for (Book book : list) {System.out.println(book.getName());}transaction.commit();} }

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02.分組查詢

/*** 分組查詢Hibernate: selectthis_.publisher_id as y0_,count(*) as y1_,sum(this_.price) as y2_ fromt_book this_ group bythis_.publisher_idHibernate: selectpublisher0_.id as id1_1_0_,publisher0_.name as name2_1_0_ fromt_publisher publisher0_ wherepublisher0_.id=?出版社：電子工業(yè)出版社, 圖書數(shù)量：3, 總價:155.0Hibernate: selectpublisher0_.id as id1_1_0_,publisher0_.name as name2_1_0_ fromt_publisher publisher0_ wherepublisher0_.id=?出版社：北京大學(xué)出版社, 圖書數(shù)量：2, 總價:67.84Hibernate: selectpublisher0_.id as id1_1_0_,publisher0_.name as name2_1_0_ fromt_publisher publisher0_ wherepublisher0_.id=?出版社：人民郵電出版社, 圖書數(shù)量：2, 總價:107.2*/ @Test public void run2() {Session session = HibernateUtil.getCurrentSession();Transaction transaction = session.beginTransaction();// 穿件criteria查詢接口Criteria query = session.createCriteria(Book.class);ProjectionList pList = Projections.projectionList();pList.add(Projections.groupProperty("publisher"));pList.add(Projections.rowCount());pList.add(Projections.sum("price"));query.setProjection(pList);Publisher publisher = null;Long count = null;Double sum = null;List<Object[]> list = query.list();for (Object[] obj : list) {publisher = (Publisher) obj[0];count = (Long) obj[1];sum = (Double) obj[2];System.out.println("出版社：" + publisher.getName() + ", 圖書數(shù)量：" + count + ", 總價:" + sum);}transaction.commit(); }

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03.聚合函數(shù)

/*** 聚合函數(shù)Hibernate: selectsum(this_.price) as y0_,min(this_.price) as y1_,max(this_.price) as y2_,avg(this_.price) as y3_ fromt_book this_[330.04, 31.0, 70.0, 47.14857142857143]*/ @Test public void run3() {Session session = HibernateUtil.getCurrentSession();Transaction transaction = session.beginTransaction();Criteria criteria = session.createCriteria(Book.class);ProjectionList projectionList = Projections.projectionList();projectionList.add(Projections.sum("price"));projectionList.add(Projections.min("price"));projectionList.add(Projections.max("price"));projectionList.add(Projections.avg("price"));criteria.setProjection(projectionList);List<Object[]> list = criteria.list();for (Object[] objects : list) {System.out.println(Arrays.toString(objects));}transaction.commit(); }

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