I have two entities
a) Student
d) Address

I have not defined mappings between them (means in oject model I have not defined any mapping between these two but in database schema I have mapping between these two which is one to one) and for some students I may not have data in address table ....I dont want to define one to one relaion ship on object model...so my question is can I write HQL which has left Outer join ?


in SQL I fire query:- select * from student st left outer join address ad on st.studentId = ad.studentRfNum;
my DB design is :-

CREATE TABLE `student` (
`name` varchar(50) DEFAULT NULL,
`age` int(4) DEFAULT NULL,
`studentId` int(11) NOT NULL AUTO_INCREMENT,
PRIMARY KEY (`studentId`)
) ENGINE=InnoDB;

CREATE TABLE `address` (
`ADDRESSID` int(11) NOT NULL AUTO_INCREMENT,
`studentRfNum` int(11) NOT NULL,
`ADDLINE` varchar(45) NOT NULL,
`CITY` varchar(45) NOT NULL,
`STATE` varchar(45) NOT NULL,
`COUNTRY` varchar(45) NOT NULL,
PRIMARY KEY (`ADDRESSID`)
) ENGINE=InnoDB;

so is there any way to write HQL equivilant to above SQL? or is there anything which I am missing?

Actually I want to load only student object not address.....but I want only those records for whom I have address in address table.....

Hibernate does not define (left join on property = property) so you can 't build a join without mapping, but this has an exception (which i will cover below).
So this i just wanted you to know this for future.

But Hibernate does have a solution for your problem :
You can define your condition in where clause.
something like :
select a.*, p.* from Address a , Parent p
where a.studentNo = p.studentRefNo

So exception is you can have a inner join in this way without mapping.
And right, left and outer jons cant be acheived in this way.