jpa-2.0

问题 Struggling to write the following query using JPA. Oracle Query: Select * from table1 s where exists (Select 1 from table2 p INNER JOIN table3 a ON a.table2_id = p.id WHERE a.id = s.table3_id AND p.name = 'Test'); Also, would you like to point any good tutorial to write complex queries in JPA. 回答1: I will answer the example of the simple car advertisement domain (advert, brand, model) using JpaRepository, JpaSpecificationExecutor, CriteriaQuery, CriteriaBuilder : brand [one-to-many] model

问题 Struggling to write the following query using JPA. Oracle Query: Select * from table1 s where exists (Select 1 from table2 p INNER JOIN table3 a ON a.table2_id = p.id WHERE a.id = s.table3_id AND p.name = 'Test'); Also, would you like to point any good tutorial to write complex queries in JPA. 回答1: I will answer the example of the simple car advertisement domain (advert, brand, model) using JpaRepository, JpaSpecificationExecutor, CriteriaQuery, CriteriaBuilder : brand [one-to-many] model

问题 I have written an entitity class with Field LoginId and Password. Iam encrypting the passwrd and stoiring it in the db using the AES_ENCRYPT. I want to retrive only the password which is decrypted. so, im using AES_DECRYPT using NAtiveQueryis in OPen JPA 2.0. Query i have written is : Query q = em.createNativeQuery("select AES_DECRYPT(l.password,?2) from loginDetails l where l.loginID = ?1"); q.setParameter(1, loginId); q.setParameter(2, getKey()); String s = q.getSingleResult(); But im

问题 I have the followed trouble. There is an entity Distributor who is connected with the ManyToMany relationship to entity town: @Entity public class Distributor{ @ManyToMany @JoinTable( name = "GS_DISTRIBUTOR_TOWN", joinColumns = @JoinColumn(name = "CD_DISTRIBUTOR"), inverseJoinColumns = @JoinColumn(name = "CD_TOWN") ) private List<Town> towns; .... } Then the entity town is also in relation with District @Entity public class Town{ @ManyToMany(mappedBy="towns") private List<Distributor>

问题 When saving a LocalDate field (e.g. '2017-09-27') to a mySQL Date column using JPA CriteriaBuilder API, the result is different (e.g. '2017-09-26'). I have validated that my database's timezone is set to UTC using SELECT TIMEDIFF(NOW(), UTC_TIMESTAMP) as the result is '00:00:00'. I am testing this locally, and I have a timezone of GMT + 2, so my suspicion is that when the conversion occurs from LocalDate to Date , 2 hours are being deducted and producing a date 1 day before the requested date

问题 When saving a LocalDate field (e.g. '2017-09-27') to a mySQL Date column using JPA CriteriaBuilder API, the result is different (e.g. '2017-09-26'). I have validated that my database's timezone is set to UTC using SELECT TIMEDIFF(NOW(), UTC_TIMESTAMP) as the result is '00:00:00'. I am testing this locally, and I have a timezone of GMT + 2, so my suspicion is that when the conversion occurs from LocalDate to Date , 2 hours are being deducted and producing a date 1 day before the requested date

问题 When saving a LocalDate field (e.g. '2017-09-27') to a mySQL Date column using JPA CriteriaBuilder API, the result is different (e.g. '2017-09-26'). I have validated that my database's timezone is set to UTC using SELECT TIMEDIFF(NOW(), UTC_TIMESTAMP) as the result is '00:00:00'. I am testing this locally, and I have a timezone of GMT + 2, so my suspicion is that when the conversion occurs from LocalDate to Date , 2 hours are being deducted and producing a date 1 day before the requested date

问题 I am having trouble working out how to do a bulk delete of a Person object using JPA, when the Person objects contain data stored using an @ElementCollection . Any ideas on how to do this would be much appreciated. @Entity @Table(name="at_person") public class Person implements Comparable<Person> { @Id @GeneratedValue(strategy = GenerationType.AUTO) @Column(name="id") private long id = 0; @Column(name="name", nullable = true, length = 128) private String name = ""; @ElementCollection @Column

问题 I would like to have native and portable id generation on my JPA 2 entities, currently running Hibernate and MySQL When using @GeneratedValue(strategy=AUTO), hibernate defaults to the "hibernate_sequence" table on MySQL, i would like IDENTITY If i solve it using @GeneratedValue(strategy=IDENTITY), i loose Oracle/Postgres portability How can i set Hibernate to use IDENTITY as default for mysql when @GeneratedValue strategy=AUTO? 回答1: You can write your own custom generator and maybe invoke a

问题 I have a JPA (Hibernate) model...One object contains a List of other objects. If i want to run a SQL query to search BOTH objects it is relatively straightforward, I do a LEFT JOIN and do a simple LIKE %searchString% on all columns. SELECT * FROM my_db.person LEFT JOIN my_db.record ON record.person_pk WHERE .... ; I cannot convert this to a JPA style query.. The model is like this @Access(AccessType.FIELD) @Entity @Table(name = "person") public class Person { @Column(nullable = true) private