Hibernate查询方法之探析

: QBE (Query By Example)

Criteria cri = sessioncreateCriteria(Studentclass);

criadd(Examplecreate(s)); //s是一个Student对象

list crilist();

实质创建一个模版比如我有一个表serial有一个 giftortoy字段我设置serialsetgifttoy()

则这个表中的所有的giftortoy为的数据都会出来

: QBC (Query By Criteria) 主要有CriteriaCriterionOderRestrictions类组成

session = thisgetSession();

Criteria cri = sessioncreateCriteria(JdItemSerialnumberclass);

Criterion cron = Restrictionslike(customername);

criadd(cron);

list = crilist();

比较运算符

HQL运算符 QBC运算符 含义

=Restrictionseq()等于

<> Restrictionsnot(Exprissioneq()) 不等于

>Restrictionsgt()大于

>= Restrictionsge()大于等于

<= Restrictions.le()小于等于

is null Restrictions.isnull() 等于空值

is not nullRestrictions.isNotNull() 非空值

like Restrictions.like() 字符串模式匹配

and Restrictions.and() 逻辑与

and njunction()逻辑与

or Restrictions.or()逻辑或

or Restrictions.disjunction()逻辑或

notRestrictions.not() 逻辑非

in(列表) Restrictions.in()等于列表中的某一个值

ont in(列表)Restrictions.not(Restrictions.in())不等于列表中任意一个值

between x and yRestrictions.between() 闭区间xy中的任意值

not between x and y Restrictions.not(Restrictions..between()) 小于值X或者大于值y

3: HQL

String hql = "select s.name ,avg(s.age) from Student s group by s.name";

Query query = session.createQuery(hql);

list = query.list();

....

4: 本地SQL查询

session = sessionFactory.openSession();

tran = session.beginTransaction();

SQLQuery sq = session.createSQLQuery(sql);

sq.addEntity(Student.class);

list = sq.list();

mit();

5: QID

Session的get()和load()方法提供了根据对象ID来检索对象的方式。tW.wiNGWIt.COM该方式被用于事先知道了要检索对象ID的情况。