• Nhibernate查询条件表示(SQL)


    方法

    说明

    Restrictions.eq

    Restrictions.allEq

    利用Map来进行多个等于的限制

    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限定查询

    有空再添加上,代码示例。

    QBC常用限定方法

    Restrictions.eq --> equal,等于.

    Restrictions.allEq --> 参数为Map对象,使用key/value进行多个等于的比对,相当于多个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 --> 对应SQL的between子句

    Restrictions.like --> 对应SQL的LIKE子句

    Restrictions.in --> 对应SQL的in子句

    Restrictions.and --> and 关系

    Restrictions.or --> or 关系

    Restrictions.isNull --> 判断属性是否为空,为空则返回true

    Restrictions.isNotNull --> 与isNull相反

    Restrictions.sqlRestriction --> SQL限定的查询

    Order.asc --> 根据传入的字段进行升序排序

    Order.desc --> 根据传入的字段进行降序排序

    MatchMode.EXACT --> 字符串精确匹配.相当于"like 'value'"

    MatchMode.ANYWHERE --> 字符串在中间匹配.相当于"like '%value%'"

    MatchMode.START --> 字符串在最前面的位置.相当于"like 'value%'"

    MatchMode.END --> 字符串在最后面的位置.相当于"like '%value'"

    例子 查询年龄在20-30岁之间的所有学生对象 List list = session.createCriteria(Student.class).add(Restrictions.between("age",new Integer(20),new Integer(30)).list(); 查询学生姓名在AAA,BBB,CCC之间的学生对象 String[] names = {"AAA","BBB","CCC"}; List list = session.createCriteria(Student.class).add(Restrictions.in("name",names)).list(); 查询年龄为空的学生对象 List list = session.createCriteria(Student.class).add(Restrictions.isNull("age")).list(); 查询年龄等于20或者年龄为空的学生对象 List list = session.createCriteria(Student.class).add(Restrictions.or(Restrictions.eq("age",new Integer(20)),Restrictions.isNull("age")).list();

    -------------------------------------------------------------------- 使用QBC实现动态查询 public List findStudents(String name,int age){

    Criteria criteria = session.createCriteria(Student.class);if(name != null){criteria.add(Restrictions.liek("name",name,MatchMode.ANYWHERE));}if(age != 0){criteria.add(Restrictions.eq("age",new Integer(age)));}criteria.addOrder(Order.asc("name"));//根据名字升序排列return criteria.list(); }

    -----------------------------------------------------------------------------------

    今天用了写hibernate高级查询时用了Restrictions(当然Expression也是可以以的)这个类.感觉不错. 下面的代码写的不易读.其实核心就是一句 Restrictions.or(Restrictions.like(),Restrictions.or(Restrictions.like,........)) 里面的or可以无限加的.还是比较好用
    Session session = getHibernateTemplate().getSessionFactory() .openSession(); Criteria criteria = session.createCriteria(Film.class); List<Film> list = criteria.add( Restrictions.or(Restrictions.like("description", key,MatchMode.ANYWHERE), Restrictions.or(Restrictions.like("name", key,MatchMode.ANYWHERE), Restrictions.or( Restrictions.like("direct", key,MatchMode.ANYWHERE), Restrictions.or(Restrictions.like("mainplay",key,MatchMode.ANYWHERE), Restrictions.like("filearea", key,MatchMode.ANYWHERE)))))).list();
    session.close(); return list;

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  • 原文地址:https://www.cnblogs.com/yisheng/p/2705069.html
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