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JPA : How to define @NamedEntityGraph for 3 levels?

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问题 I have 3 entities. Branch,Subject,Topic. Branch has list of subjects and Subject has list of topics. Also subjectList and topicList both are lazy. I want to fetch all branch including its subjects and topics in single query. 1. @Entity public class Branch implements Serializable { private static final long serialVersionUID = 1L; @Id @GeneratedValue(strategy = GenerationType.AUTO) private Integer id; private String name; @OneToMany(mappedBy = "branch") private List<Subject> subjectList; /

How to register non-standarized SQL functions manually in Spring Boot application?

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I'm using JPA query in my current spring-boot project. How can I add non-standardized SQL functions like GROUP_CONCAT ? Prior, to my previous problem : How to show a column result in a one line comma separated list in JPA query I found that GROUP_CONCAT is not a registered function in JPA query but could be accessed by registering it manually. I already tried following links but didn't work for me : How to add non-standardized sql functions in Spring Boot application? Registering a SQL function with JPA and Hibernate https://thoughts-on-java.org/database-functions/ https://vladmihalcea.com

JPA join entity on the same entity

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I have a question about JPQL. I need to join entity on the same entity. Entity.child_id is mapped as a collection in JPA entity class, i.e. entity have a collection property ("children") which holds every child. Join works fine with this collection (don't know why, by the way), for example: SELECT parent.id, child FROM Entity parent JOIN parent.children child The question is, is there a way to write this query without JOIN, something like this: SELECT parent.id, child FROM Entity parent, Entity child WHERE <condition> I don't know how to construct a condition. "parent.children = child" doesn't

JPQL Not a Selected Expression error

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I have the following JPQL in ProductList Entity class which executes as expected. select DISTINCT new foo.bar.ProductListDTO(p.prodId, " + CASE WHEN (p.prodId = 'ZCX') THEN CONCAT(p.prodDesc, ' - ', e.userId) ELSE p.prodDesc END) from ProductList p LEFT JOIN p.productCatalogueList c where c.userId='ZAM' ProductListDTO class public ProductListDTO(String prodId, String prodDesc, String userId) { this.prodId = prodId; this.prodName = prodDesc; this.userId = userId; } What I would like to achieve is add ORDER BY to the query. When p.prodDesc is added to ORDER BY clause, I am getting error not a

Why does a manually defined Spring Data JPA delete query not trigger cascades?

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问题 I have following problem: when I try to delete an entity that has following relation: @OneToMany(mappedBy="pricingScheme", cascade=CascadeType.ALL, orphanRemoval=true) private Collection<ChargeableElement> chargeableElements; with a CrudRepository through a provided delete method it removes the entity along with its all chargeable elements which is fine. The problem appears when I try to use my custom delete: @Modifying @Query("DELETE FROM PricingScheme p WHERE p.listkeyId = :listkeyId") void

How to create a request for a complex query? @Query jpql spring jpa

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问题 How to create a request for a complex query in JpaRepository with the use of @Query ? I am concerned about the relationships between entities. They may affect the preparation of the request. Needed query SQL, my version @Query: 回答1: Ok so more advisable way of declaring your query would be : @Query( "SELECT bu.email " + "FROM Businesscentr bu INNER JOIN bu.bannersSet bs INNER JOIN bs.clicks c " + "WHERE c.fullNameClient = :fullNameClient" // optional ) You only use the old join style when you

How do I reuse a parameter witha Spring-Data-JPA Repository?

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In looking at the Query Creation for the Spring Data JPA Repositories, I'm wondering how I would reuse a parameter. For example, how would I name the method if I wanted to do something like: @Query("select c from #{#entityName} c where c.lower <= ?1 and c.upper >= ?1") E findByConversionFor(Double amount); Can that query be converted to a SpEL method name (to be used by the query builder)? It seems like a kludge to require the same value to be passed twice: E findByLowerLessThanOrEqualAndUpperGreaterThanOrEqual(Double a, Double b); // where a==b Just mark your parameter with @Param("amount")

Spring Data JPA JPQL queries on parent interface

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Say I have a @MappedSuperClass like this: @MappedSuperclass public abstract class Rating { @Id private Long id; @Column(name="USER_ID") private Long userId; private int rating; ... With a concrete child entity like this @Entity @Table(name="ACTIVITY_RATING") public class ActivityRating extends Rating { private Long activitySpecificData; ... Then there is a Spring Data JPA repository like this: @NoRepositoryBean public interface RatingRepository<R extends Rating> extends JpaRepository<R, ID> { public List<R> findByUserId(Long userId); ... and this: public interface ActivityRatingRepository

How can i inner join a subquery in JPQL

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问题 I need a JPQL for the MySQL query: SELECT * FROM table1 t1 INNER JOIN table2 t2 ON t1.id = t2.table1.id INNER JOIN (SELECT * FROM table1 t3 INNER JOIN table2 t4 ON t3.id = t4.table1.id WHERE t3.name = 'xxx') subTable ON t1.number = subTable.number WHERE t1.number = '5' AND id = '3' 回答1: Your query seems quite pathological, perhaps say what result you are trying to query, and include your object model. In general, JPQL does not support sub-selects in the from clause, so your query is not

JPA - using long array in IN operator throws cast exception

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am new to JPA and am able to get it quickly, I had been trying a select query using "IN" operator in the query and had been getting the error as down. What I do is, i get a array of (long) message ids from a function and i use it to select the record based on those ids. Here is my query select t from MessageTable t where t.messageId IN (:id) query.setParameter("id", id); I had just shown you part of the code, in entity messageId is long and in Oracle DB its number. When i try as just as long variable it works, it doesn't seem to work when i pass long array. Had any one come across such a