hql的几种写法



Java代码







String sql = "select * from T_TMP_PUBLIC_POLICY TP"; SQLQuery sqluery = session.createSQLQuery(sql).addEntity(TPublicPolicyTemporary.class); List tmpList = sqluery.list();

String sql = "select * from T_TMP_PUBLIC_POLICY TP";
SQLQuery sqluery = session.createSQLQuery(sql).addEntity(TPublicPolicyTemporary.class);

List tmpList = sqluery.list();

注册到非 Hibernate pojo 中：

Java代码







sess.createSQLQuery("SELECT NAME, BIRTHDATE FROM CATS") .setResultTransformer(Transformers.aliasToBean(CatDTO.class))

sess.createSQLQuery("SELECT NAME, BIRTHDATE FROM CATS")
.setResultTransformer(Transformers.aliasToBean(CatDTO.class))

返回多个实体

Java代码







sess.createSQLQuery("SELECT {cat.*}, {mother.*} FROM CATS c, CATS m WHERE c.MOTHER_ID = c.ID")
.addEntity("cat", Cat.class)
.addEntity("mother", Cat.class)

{cat.*}, 的cat 就是 addEntity（“ 里面的 cat 名称。

select new xxx(a1,a2,a3) from bbbb

参考：/article/4194075.html

other:

Finder finder = Finder

.create("select a,b from SysRole a,SysDepart b where a.departGuid=b.departGuid");

Pagination pagination = find(finder, pageNo, pageSize);

List<?> tempList=pagination.getList();

List<SysRole> lsReslut=new ArrayList();

for (Object object : tempList) {

SysRole tempRole=(SysRole)((Object[])object)[0];

SysDepart tempDepart=(SysDepart)((Object[])object)[1];

tempRole.setSysDepart(tempDepart);

}

对于支持子查询的数据库，Hibernate支持在查询中使用子查询。一个子查询必须被圆括号包围起来（经常是SQL聚集函数的圆括号）。 甚至相互关联的子查询（引用到外部查询中的别名的子查询）也是允许的。

from Cat as fatcat
where fatcat.weight > (
select avg(cat.weight) from DomesticCat cat
)

from DomesticCat as cat
where cat.name = some (
select name.nickName from Name as name
)

from Cat as cat
where not exists (
from Cat as mate where mate.mate = cat
)

from DomesticCat as cat
where cat.name not in (
select name.nickName from Name as name
)

select cat.id, (select max(kit.weight) from cat.kitten kit)
from Cat as cat

注意，HQL自查询只可以在select或者where子句中出现。
在select列表中包含一个表达式以上的子查询，你可以使用一个元组构造符（tuple constructors）：

from Cat as cat
where not ( cat.name, cat.color ) in (
select cat.name, cat.color from DomesticCat cat
)

注意在某些数据库中（不包括Oracle与HSQL），你也可以在其他语境中使用元组构造符， 比如查询用户类型的组件与组合：

from Person where name = ('Gavin', 'A', 'King')

该查询等价于更复杂的：

from Person where name.first = 'Gavin' and name.initial = 'A' and name.last = 'King')

有两个很好的理由使你不应当作这样的事情：首先，它不完全适用于各个数据库平台；其次，查询现在依赖于映射文件中属性的顺序。