HQL: illegal attempt to dereference collection

[Rohit Bhal]

The situation is like this:

I have an entity Book that holds a one-to-many relationship with Chapter.

Now if I try the query, "from Book book inner join book.chapters chapter where chapter.title like '%hibernate%'", it gives me the desired result.

But if I try, "from Book where book.chapters.title like '%hibernate%'", I get the error illegal attempt to dereference collection.

The thing is that I only want the collection of Book objects in return and not a collection of pair of Book and Chapter objects in return which I get with the former query.

Could someone help me understand?

[Bogdan Baraila]

Hello.
You can also try with: "select distinct ch.book from Chapter ch where ch.title like '%hibernate%'"

[joy b chakravarty]

But if I try, "from Book where book.chapters.title like '%hibernate%'", I get the error illegal attempt to dereference collection.

This would not work... as its something like book.getChapters().getTitle() .. as as book.getChapters() returns a collection, the getTitle fails.

[Rohit Bhal]

@joy: I think query like "...book.chapters.title..." is not supported anymore. I am not sure if it was supported in the older version of Hibernate either. Thanks for reply

@Bogdan: Yes, "select book from Book book inner join book.chapters chapter where chapter.title like '%Hibernate%'" gave me exactly that. Thanks for reply