Hibernate version: 3.1.3

I need to create a left outer join between two tables that have no mapping relationship. From what I've seend I need to create a mapping relationship between the two tables. Is there a way to create a left outer join without using a mapping relationship.

Well from what I have investigated the only way to use an outer join is using a path. There is no way with Hibernate to do:

select *
from tablea a left outer jin tableb b on a.col1 = b.col2

without using an existing one-to-many or many-to-many mapping

Hi, same problem here. I cannot belive that this is not possible.
The join ... on syntax should be supported, shouldn't it?

thanks

Hi, same problem. Is this a missing functionality, or is this normal in Hibernate programming model? If this is normal, than what should we do to solve this problem?

Thanks.

it looks like a missing functionality

This kind of join can be done in Hibernate using "theta-style" joins (the old way to join).

For example - instead of:

select *
from tablea a left outer jin tableb b on a.col1 = b.col2

Use this syntax:

from tablea a, tableb b
where a.col1 = b.col2

Each row in the result would be an Object array with 2 elements, the first would be tablea (the corresponding object), the second would be tableb.

You can also use this syntax so that each row will be a map:

select new map(a as ta, b as tb) from tablea a, tableb b ...

Now each row will be a map:
{ta=tablea object, tb=tableb object}

HTH

The solution shown



doesn't really return an outer join but a inner join, right ?

That is, you won't have a if b doesn't exist...

is there any other solution for that ?

I'm having the same problem as I try to convert a lot of native SQL queries into HQL. If it has to be kept as native SQL, is there an easy way to do a mapping in native SQL like in HQL such as:


Thanks