JPA/Hibernate Fundamentals 2023 - Lesson 14 - Join and subqueries with criteria query

[@derzerstorer9001]

Thank you very much for this tutorial! Learned a lot from this🤗

[@laurspilca]

Happy to hear!

[@rohitgupta025]

Great Video, Excellent Knowledgeable stuff, one small suggestion , please zoom MySQL workbench

[@laurspilca]

Code on GitHub: github.com/lspil/youtubechannel/tree/master/jpa_2023_c14_e1

[@mohammedhegazy1778]

I think you forget to put the schema for my sql database for this lesson in github

[@laurspilca]

@@mohammedhegazy1778 Hello. I didn't because I simply let Hibernate generate it. This is ok for learning, but remember not use do this in real life apps :)

[@mohammedhegazy1778]

I know that but instead of adding data to tables manually and takes times only for that 😂😂@@laurspilca

[@jaswanthreddyputluru4889]

heyy laur , what if i dont want my hibernate to create tables and say i created join tables by myself , now how hibernate knows which table to refer , hwo to make sure that hibernate uses specific join table when there are multiple join tables for example in this lesson there are 2 join tables , i totally understood the situation when hibernate creates tables because it knows what it created but what if in other case ?

[@zabialy2919]

I have trouble doing pagination when joining. I have an Parent Entity A which has a collection of children B. When joining them, and setting first result to 0 and max results to 10. I expect having 10 results. But when the children B are for example 2 per parent entity A. I only get 5 results. It seems all the Entities together count. How can I avoid that and implement pagination, while joining the Entities? Thanks in advance! :)

[@OsteenOmega]

Hello sir. if i have an application with many joins and queries, can i use stored procedures? or should i just use jpql queries in jpa? which one do you recommend

[@laurspilca]

Hello. Difficult to answer this one. It really depends on many things and unless I investigate a case I cannot give advice.

[@zabialy2919]

Is there a way to do a join with entity inheritance? I have the InheritanceType.JOINED. There is an abstract parent Entity with generic data. The Entity extending has it own specific data, and by inheritance the parents general data. As there will be more specific extending entities. I want to have my relationships with other tables on the abstract parent Entity. So the aim is to join the specific Entity with the generic one and then with the other table in order to filter the data based on the join. Or is the only option to add the relationship owning to all specific (these extending the parent entity) Entities.

[@laurspilca]

Hi. Not sure I understand. An entity cannot be abstract. If it's abstract then it should be a mapped superclass.

[@zabialy2919]

@@laurspilca Ok, I don't know why but after your answer I got on track to find my solution. By the way your videos are very helpful. Greetings from Poland!

[@laurspilca]

@@zabialy2919 Cool!