| HQL運算符 |
QBC運算符 |
含義 |
| = |
Restrictions.eq() |
等於equal |
| <> |
Restrictions.ne() |
不等於not equal |
| > |
Restrictions.gt() |
大於greater than |
| >= |
Restrictions.ge() |
大於等於greater than or equal |
| < |
Restrictions.lt() |
小於less than |
| <= |
Restrictions.le() |
小於等於less than or equal |
| is null |
Restrictions.isnull() |
等於空值 |
| is not null |
Restrictions.isNotNull() |
非空值 |
| like |
Restrictions.like() |
字符串模式匹配 |
| and |
Restrictions.and() |
邏輯與 |
| and |
Restrictions.conjunction() |
邏輯與 |
| or |
Restrictions.or() |
邏輯或 |
| or |
Restrictions.disjunction() |
邏輯或 |
| not |
Restrictions.not() |
邏輯非 |
| in(列表) |
Restrictions.in() |
等於列表中的某一個值 |
| not in(列表) |
Restrictions.not(Restrictions.in()) |
不等於列表中任意一個值 |
| between x and y |
Restrictions.between() |
閉區間xy中的任意值 |
| not between x and y |
Restrictions.not(Restrictions..between()) |
小於值X或者大於值y
|
2，QBC常用限定方法
Restrictions.eq --> equal,等於.
Restrictions.allEq --> 參數為Map對象,使用key/value進行多個等於的比對,相當於多個Restrictions.eq的效果
Restrictions.gt --> great-than > 大於
Restrictions.ge --> great-equal >= 大於等於
Restrictions.lt --> less-than, < 小於
Restrictions.le --> less-equal <= 小於等於
Restrictions.between --> 對應SQL的between子句
Restrictions.like --> 對應SQL的LIKE子句
Restrictions.in --> 對應SQL的in子句
Restrictions.and --> and 關系
Restrictions.or --> or 關系
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 --> 根據傳入的字段進行升序排序
Order.desc --> 根據傳入的字段進行降序排序
MatchMode.EXACT --> 字符串精確匹配.相當於"like 'value'"
MatchMode.ANYWHERE --> 字符串在中間匹配.相當於"like '%value%'"
MatchMode.START --> 字符串在最前面的位置.相當於"like 'value%'"
MatchMode.END --> 字符串在最后面的位置.相當於"like '%value'"
例子
查詢年齡在20-30歲之間的所有學生對象
List list = session.createCriteria(Student.class)
.add(Restrictions.between("age",new Integer(20),new Integer(30)).list();
查詢學生姓名在AAA,BBB,CCC之間的學生對象
String[] names = {"AAA","BBB","CCC"};
List list = session.createCriteria(Student.class)
.add(Restrictions.in("name",names)).list();
查詢年齡為空的學生對象
List list = session.createCriteria(Student.class)
.add(Restrictions.isNull("age")).list();
查詢年齡等於20或者年齡為空的學生對象
List list = session.createCriteria(Student.class)
.add(Restrictions.or(Restrictions.eq("age",new Integer(20)),
Restrictions.isNull("age")).list();
--------------------------------------------------------------------
使用QBC實現動態查詢
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"));//根據名字升序排列
return criteria.list();
}
public List findByCriteria(Object[] args) {
return HibernateSessionFactory
.getSession()
.createCriteria(Emp.class)
// and
.add(Restrictions.eq("id", 123))
.add(Restrictions.gt("hriedate", "1985-4-1"))
.add(Restrictions.ge("hriedate", "1985-4-1"))
.add(Restrictions.lt("hriedate", "1985-4-1"))
.add(Restrictions.le("hriedate", "1985-4-1"))
// or
.add(Restrictions.or(Restrictions.eq("id", 123),
Restrictions.gt("hriedate", "1985-4-1")))
// 多個or
.add(Restrictions.disjunction().add(Restrictions.eq("id", 123))
.add(Restrictions.gt("hriedate", "1985-4-1"))
.add(Restrictions.ge("hriedate", "1985-4-1")))
// 各種條件
.add(Restrictions.between("age", "19", "25"))
// 張(STRAT是張在開頭（END是張在后頭）（ANYWHERE任何位置）（EXACT嚴格匹配）)%
.add(Restrictions.like("name", "zhang", MatchMode.START))
.add(Restrictions.ilike("name", "zhang"))
// 忽略大小寫
.add(Restrictions.in("id", args))
.add(Restrictions.isEmpty("emps"))
// Dept.emps(針對集合) 沒有員工的部門
.add(Restrictions.isNotEmpty("emps"))
.add(Restrictions.not(Restrictions.isEmpty("emps")))// 給某些不帶一對的條件取反用的
.add(Restrictions.isNull("sal"))// sal is null
.add(Restrictions.isNotNull("sal"))// sal is not null
.add(Restrictions.sizeEq("emps", 5))// 查詢部門人數等於 5個的
.add(Restrictions.eq("id", 5)).add(Restrictions.ne("id", 5))// 不等於5
.add(Restrictions.eqProperty("birthday", "hiredate"))// 兩個屬性相等，其他屬性也一樣F
.list();
}
}