jpa-2.0

I am new to JPA, when I tried to run the following code, it showing error as " cvc-elt.1: Cannot find the declaration of element 'persistence'. " I cant able to fix this error, could u pls help me out to solve this issue. Cheers Rajesh Persistance.xml <?xml version="1.0" encoding="UTF-8"?> <persistence version="2.1" xmlns="http://xmlns.jcp.org/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd"> <persistence-unit name="jpa" transaction-type="JTA">

How can I, using the JPA criteria API do the following: select count(distinct column1, column2) from table Doing this on one column/path is simple using CriteriaBuilder.countDistinct, but how can I do this on two paths/columns? ryenus Here is a late answer :-) though I'm not sure if things had changed. Recently I encountered the very same need, and worked around it using concat, i.e., by concatenating the columns into a pseudo column , then countDistinct on the pseudo column. But I couldn't use criteriaBuilder.concat because it generated JPQL using || for the concatenation, which Hibernate had

There is this table that is being generated on a monthly basis. Basically the table structure of all monthly tables is the same. Since it would be a lot of work to map the same entity just with a different table name, Is it possible to change the table name of an entity as follows on runtime since they have the same table structure after all? @Entity @Table(name="FOO_JAN2010") // any other ways to generate this dynamically? public class FooJan2010Table { // if we can dynamically set the table name this can be simply named FooTable ... } If not, what approach can you suggest? Pascal Thivent Is

I have an an object (BlogPost) that contains an M:N collection of elements (Tags). How to query for an object (BlogPost) where at least one it its Tags matches an element in a set of Tags (defined by the user) with JPA2 (Hibernate). findBlogPostWithAtLeastOneMatchingTag(Collection<Tag> tags){ ???? } My main problem is, that I actually need to compare two collections of tags: - the collection of tags of the BlogPost. - the collection I search for I tried Select p from Post p where p.tags in(:tags) but it does not work, as my post entities have more than just one tag. So what could I do instead?

I want to use criteria to make the following query. I have an Entity with EmbeddedId defined: @Entity @Table(name="TB_INTERFASES") public class Interfase implements Serializable { @EmbeddedId private InterfaseId id; } @Embeddable public class InterfaseId implements Serializable { @Column(name="CLASE") private String clase; } And the criteria query that i am trying to do is: CriteriaBuilder criteriaBuilder = this.entityManager.getCriteriaBuilder(); CriteriaQuery<Interfase> criteriaQuery = criteriaBuilder.createQuery(Interfase.class); Root<Interfase> entity = criteriaQuery.from(Interfase.class);

I am using spring data JPA in my project. I am playing with millions of records. I have a requirement where I have to fetch data for various tables and build a object and then paint it on a UI. Now how to achieve this my Spring data Repositories. I have read that it can be achieved by Named native queries. If the named native query does not return an entity or a list of entities, we can map the query result to a correct return type by using the @SqlResultSetMapping annotation. But when I am trying to use @SqlResultSetMapping it is taking another entityResult . Mean what I understand is that it