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How to paginate a #Query query that is sorted? Java

#Query("select p.id,m.id,c.tipoDocumento,c.codigoFact from Corresponsable c"
" inner join Pais p"
" on p.id = c.pais.id"
" inner join Moneda m"
" on m.id = c.moneda.id"
" order by p.nombre,m.nombre,c.tipoDocumento,c.codigoFact")
List<Corresponsable> getFindPorCodPaisMonedaTipoDoc();
I did it this Query with JPA #Query in my Repository, but i would like to paginate my results with a number of page and numer of offset. What would be the best way to paginate keeping my values ​​ordered?

The Spring Data has native support to paginating, you can simply declare:
List<Corresponsable> getFindPorCodPaisMonedaTipoDoc(Pageable pageable).
You can manage the pagination with:
Pageable pageable = PageRequest.of(page, pageSize, Sort.by(sortBy));
For more info: https://docs.spring.io/spring-data/commons/docs/current/api/org/springframework/data/domain/Pageable.html

What is wrong or incorrect in the below JPQL query?

Below is the JPQL query I wrote but it is not working. I get the following error: NoViableAltException: unexpected token: max
Can someone please point out the error in the below query?
SELECT new com.chp.cef.api.dto.EventSearchDTO(ec.eventName, e.eventKey, e.eventTime, CAST(e.messagePayload AS string), epl.status, epl.statusReason, CAST(epl.processLogPayload AS string), ec.source, " +
"epl.eventProcessLogKey, epl.eventReceivedTime, epl.eventProcessedTime) FROM Event e " +
"left join (SELECT inEpl.eventKey, max(inEpl.eventReceivedTime), inEpl.eventProcessLogKey, inEpl.status, inEpl.statusReason, inEpl.processLogPayload, inEpl.eventProcessedTime" +
"FROM EventProcessLog inEpl GROUP BY inEpl.eventKey) epl ON e.eventKey = epl.eventKey " +
"left join EventConfiguration ec ON e.eventConfigKey = ec.eventConfigurationKey WHERE ec.eventName = coalesce(:eventName, ec.eventName) " +
"AND epl.status = coalesce(:eventStatus, epl.status) AND e.eventTime >= :eventStartTime AND e.eventTime <= :eventEndTime

You can't join a subquery in JPQL/HQL. You will have to reformulate this to a correlated subquery in the ON clause.
Having said that, I think this is a perfect use case for Blaze-Persistence Entity Views along with the it's support for fetching the TOP-N per category through the #Limit annotation.
I created the library to allow easy mapping between JPA models and custom interface or abstract class defined models, something like Spring Data Projections on steroids. The idea is that you define your target structure(domain model) the way you like and map attributes(getters) via JPQL expressions to the entity model.
But Blaze-Persistence not only helps you with the DTO mapping, it also enabled the use of some of the more advanced SQL concepts, in this case, lateral joins.
A DTO model for your use case could look like the following with Blaze-Persistence Entity-Views:
#EntityView(Event.class)
public interface EventSearchDTO {
#IdMapping
String getEventKey();
String getEventName();
Instant getEventTime();
#Mapping("CAST_STRING(messagePayload)")
String getMessagePayload();
// ...
#Limit(limit = "1", order = "eventReceivedTime DESC")
#Mapping("EventProcessLog[eventKey = VIEW(eventKey)]")
// If you have an association mapping, can be simplified to
// #Mapping("processLogs")
EventProcessLogDto getLatestLog();
#EntityView(EventProcessLog.class)
interface EventProcessLogDto {
#IdMapping
String getEventKey();
String getEventProcessLogKey();
// ...
}
#Mapping("EventConfiguration[eventConfigurationKey = VIEW(eventConfigKey)]")
EventConfigurationDto getConfiguration();
#EntityView(EventConfiguration.class)
interface EventConfigurationDto {
#IdMapping
String getEventConfigurationKey();
// ...
}
}
Querying is a matter of applying the entity view to a query, the simplest being just a query by id.
EventSearchDTO a = entityViewManager.find(entityManager, EventSearchDTO.class, id);
The Spring Data integration allows you to use it almost like Spring Data Projections: https://persistence.blazebit.com/documentation/entity-view/manual/en_US/index.html#spring-data-features
This will produce a SQL query similar to the following
SELECT ec.eventName, ...
FROM Event e
left join lateral (SELECT * FROM EventProcessLog inEpl WHERE e.eventKey = inEpl.eventKey ORDER BY inEpl.eventReceivedTime DESC LIMIT 1) epl ON 1=1
left join EventConfiguration ec ON e.eventConfigKey = ec.eventConfigurationKey

How to load #ElementCollection within custom query?

I want to reduce the amount of querys run by spring. When getting an object with #ElementCollection via SQL I want to get the data for the ElementCollections directly via a JOIN within the quers.
The attribute with the ElementCollection
#ElementCollection(fetch = FetchType.EAGER)
#JoinTable(name = "song_genre_list")
#org.hibernate.annotations.Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
private List<String> genre;
The Method that uses a custom string:
#Query(
value = "select distinct s.*, g.* from musicdb.songs s left join musicdb.song_genre_list g on s.id = g.song_id where s.name like ?1 or s.artist like ?1",
nativeQuery = true)
List<Song> searchSong(String title);
How I would imagine defining a query that also loads this element collection:
SELECT DISTINCT s.*, g.* FROM musicdb.songs s LEFT JOIN musicdb.song_genre_list g ON s.id = g.song_id WHERE s.name LIKE ?1 OR s.artist LIKE ?1
What Spring currently does (loading the genres for 3 songs with more querys):
Hibernate: select distinct s.*, g.* from musicdb.songs s left join musicdb.song_genre_list g on s.id = g.song_id where s.name like ?1 or s.artist like ?1
Hibernate: select genre0_.song_id as song_id1_4_0_, genre0_.genre as genre2_4_0_ from musicdb.song_genre_list genre0_ where genre0_.song_id=?
Hibernate: select genre0_.song_id as song_id1_4_0_, genre0_.genre as genre2_4_0_ from musicdb.song_genre_list genre0_ where genre0_.song_id=?
Hibernate: select genre0_.song_id as song_id1_4_0_, genre0_.genre as genre2_4_0_ from musicdb.song_genre_list genre0_ where genre0_.song_id=?
What I want Spring to do:
Hibernate: select distinct s.*, g.* from musicdb.songs s left join musicdb.song_genre_list g on s.id = g.song_id where s.name like ?1 or s.artist like ?1
The required Data for the ElementCollection is already included with the join. How can I tell spring to import that Data?

FetchType.EAGER will already load the genres for you, so you dont need to write a join in your original query. But for that hibernate hibernate uses separate queries by default. To change this add the annotation '#Fetch(FetchMode.JOIN)' on the genre field

Jpa namedquery with left join fetch

this is my namedquery:
#NamedQuery(
name = "User.findOneWithLists",
query = "SELECT u FROM User u "
+ "LEFT JOIN FETCH u.aTemplates "
+ "LEFT JOIN FETCH u.bTemplates "
+ "LEFT JOIN FETCH u.bp "
+ "LEFT JOIN FETCH u.aCredentials "
+ "LEFT JOIN FETCH u.st WHERE (st.deleted = false) "
+ "LEFT JOIN FETCH u.bCredentials "
+ "LEFT JOIN FETCH u.cl "
+ "WHERE u.id= :id")
My problem is that I get an error when the application starting:
org.hibernate.hql.internal.ast.QuerySyntaxException: unexpected token: LEFT ....
On the st side there is an annotation
#ManyToOne
#JoinColumn(name = "st_user")
private User user;
Any idea how can I handle this where clause?

Check a SQL syntax, you can't use left join after where clause. If you are looking at the SQL generated form that named query you will see that joined tables in the query the where clause comes after joins and should specify equal condition that links those tables by the keys. The primary key of the main table on the left and the foreign key of the joined table on the right. The joined table is specified by the property of your many-to-one association.
#NamedQuery(
name = "findOneWithLists",
query = "from Table t left join User u where u.id= :id"
)

For join conditions Hibernate provides the with keyword, even before JPA 2.1.
The relevant part of your query thus would look like this:
SELECT u FROM User u ... LEFT JOIN u.st WITH st.deleted = false
I'm not sure about LEFT JOIN FETCH u.cl with u.id= :id but if I remember correctly, that's not as easy and might have to be resolved with an adapted join and u.ui = :id in the where condition.
LEFT JOIN FETCH u.st WITH st.deleted = false`
This is not supported, since you can't do a partial fetch.

Complex SQL query to Hibernate HQL statement

Following SQL query:
select distinct hotel.country 'Country', hotel.id 'Hotel ID', hotel.Name'Name', room.id 'Room ID'
from room, stay, reservation, hotel
where
(stay.roomid = room.id)
and (stay.reservationid = reservation.id)
and (reservation.status != 'Booked' AND reservation.status != 'CheckedIn')
and (reservation.arrivaldate >= '2012-08-08')
and (reservation.leavedate <= '2012-08-15')
and (room.hotelid = hotel.id)
order by hotel.country, hotel.id, hotel.name, room.id asc
This will give me a list of available rooms per hotel per country. Now I have to put this in HQL, but I can't do so because of this:
Query query = session.createQuery("from room, stay, reservation, hotel where stay.roomid = room.id");
This doesn't work becuase stay.roomid is a Room object whereas room.id is just an integer. I'm pretty new to Hibernate/HQL and the reference manual didn't really bring me anywhere... How can I "convert" (scary word, I know this doesn't involve actual converting) this SLQ query to a HQL statement? Thanks.
UPDATE
Using a join result in the same problem
Query query = session.createQuery("" +
"from Stay stay " +
"join stay.ReservationID reservation " +
"join stay.RoomID room " +
"join room.HotelID hotel " +
"where (stay.RoomID = room.ID)");
I'm really missing something (probably very logical) here...

You haven't shown your entities, but, just as you would use joins in SQL, you need to use joins in HQL:
select ...
from Stay stay
join stay.reservation reservation
join stay.room room
join rom.hotel hotel
where (reservation.status != 'Booked' AND reservation.status != 'CheckedIn')
and (reservation.arrivaldate >= '2012-08-08')
and (reservation.leavedate <= '2012-08-15')
The Hibernate documentation has a whole chapter on HQL, and a section of this chapter about associations in HQL.