QBC常用限定方法

Restrictions.eq --> equal,等于.

Restrictions.allEq --> 參數(shù)為Map對(duì)象,使用key/value進(jìn)行多個(gè)等于的比對(duì),相當(dāng)于多個(gè)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(duì)應(yīng)SQL的between子句

Restrictions.like --> 對(duì)應(yīng)SQL的LIKE子句

Restrictions.in --> 對(duì)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(xún)

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'"

例子
查詢(xún)年齡在20-30歲之間的所有學(xué)生對(duì)象
List list = session.createCriteria(Student.class)
      .add(Restrictions.between("age",new Integer(20),new Integer(30)).list();
查詢(xún)學(xué)生姓名在AAA,BBB,CCC之間的學(xué)生對(duì)象
String[] names = {"AAA","BBB","CCC"};
List list = session.createCriteria(Student.class)
      .add(Restrictions.in("name",names)).list();
查詢(xún)年齡為空的學(xué)生對(duì)象
List list = session.createCriteria(Student.class)
      .add(Restrictions.isNull("age")).list();
查詢(xún)年齡等于20或者年齡為空的學(xué)生對(duì)象
List list = session.createCriteria(Student.class)
      .add(Restrictions.or(Restrictions.eq("age",new Integer(20)),
                 Restrictions.isNull("age")).list();

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使用QBC實(shí)現(xiàn)動(dòng)態(tài)查詢(xún)
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"));//根據(jù)名字升序排列
 return criteria.list();
}