Question

My code is to select the text from the parameter :title. But I got the result which is not right. In my case, class Book extends Media.

This is my query.

String queryStr = "SELECT DISTINCT(b) FROM Book b, Media m  WHERE lower(m.title) LIKE :title"
TypedQuery<Book> query = em.createQuery(queryStr, Book.class);
if (book.getTitle() != null && book.getTitle() != "")
            query.setParameter("title", "%" + book.getTitle().toLowerCase() + "%");

My parameter is “harry”. I suppose to get only 1 result but I got all the data that I have.
What is the mistake from my code? please help.

Answer 1

You should leave Media out of the query. JPA also knows Book extends Media so it knows where to get the Media part of the books.