I have and entity lets call it Entity, and a Child collection Children. I have a screen where the user has the Entity information, and a list with the Children collection, but that collection can be get very big, so i was thinking about using paging: get the first 20 elements, and lazy load the next only if the user explicitly presses t...
Given these tables: create table Orders ( Id INT IDENTITY NOT NULL, primary key (Id) ) create table Items ( Id INT IDENTITY NOT NULL, primary key (Id) ) create table OrdersItems ( OrderId INT not null, ItemId INT not null, primary key (OrderId, ItemId) ) Is it possible to use HQL/criteria API to contruct a query...
Hello all, I am a bit stucked constructing a dynamic query using the CriteriaBuilder of JPA 2.0. I have quite a common use case I guess: User supplies a arbitrary amount of search parameters X to be and / or concatenated: like : select e from Foo where (name = X1 or name = X2 .. or name = Xn ) The Method or of CriteriaBuilder is no...
How can I write the below HQL query using the Criteria API? select s.Name, sum(q.PointsObtained), sum(q.TotalPoints) from Student s join s.Quizzes q group by s.Name order by (sum(q.PointsObtained) / sum(q.TotalPoints)) desc ...
I'm having trouble figuring out how to represent the following JPQL query: SELECT count(e) FROM Foo e using Criteria API. What I'm trying is: CriteriaBuilder cb = em.getCriteriaBuilder(); CriteriaQuery<Foo> c = cb.createQuery(Foo.class); Root<Foo> f = c.from(Foo.class); c.select(cb.count(f)); but this is not working. I also tried: ...
Hello there ! I'm trying to create a query with the Criteria API from JPA 2.0, but I can't make it work. The problem is with the "between" conditional method. I read some documentation to know how I have to do it, but since I'm discovering JPA, I don't understand why it does not work. First, I can't see "creationDate" which should app...
I have got two entities Person and Book. Only one instance of a specific book is stored to the system (When a book is added, application checks if that book is already found before adding a new row to the database). Relevant source code of the entities is can be found below: @Entity @Table(name="persons") @SequenceGenerator(name="id_seq...
I am trying to get a list of Products that share the Category. NHibernate returns no product which is wrong. Here is my Criteria API method : public IList<Product> GetProductForCategory(string name) { return _session.CreateCriteria(typeof(Product)) .CreateCriteria("Categories") .Ad...
I need a generic Criterion which forces the result to zero matches. Something like Restrictions.eq(true, false) ? ...
public class Entity { public virtual string Title { get; set; } public virtual DateTime CreationDate { get; set; } public virtual int Count { get; set; } } I have a problem when creating Criteria for a given entity: var s = session.CreateCriteria<Entity>() .Add(Expression.Ge("CreationD...
I have to following entity object @Entity public class Foobar { ... private List<String> uuids; ... } Now I'd like to make a criteria query which would fetch all Foobar pojos whose uuids list contains the string "abc123", I'm just not sure how to make the appropriate criterion. ...
Say I have two entities Foo and Bar where Foo has-many Bar's, class Foo { int ImportantNumber { get; set; } IEnumerable<Bar> Bars { get; set; } } class FooDTO { Foo Foo { get; set; } int BarCount { get; set; } } How can I efficiently sum up the number of Bars per Foo in a DTO using a single query, preferrably only with the Cr...
I have an entity A which HasMany entities B and entities C. All entities A, B and C have some references x,y and z which should be loaded eagerly. I want to read from the database all entities A, and load the collections of B and C eagerly using criteria API. So far, I am able to fetch the references in 'A' eagerly. But when the collec...
This seems like a pretty simple question, but I have not managed to find a definitive answer yet. I have a DAO class, which is naturally querying the database by using criteria queries. So I would like to know if it is safe to use the same CriteriaBuilder implementation for the creation of different queries or do I have to create new Cri...
Consider the following Class structure... public class ListViewControl { public int SystemId {get; set;} public List<ControlAction> Actions {get; set;} public List<ControlAction> ListViewActions {get; set;} } public class ControlAction { public string blahBlah {get; set;} } I want to load class ListViewControl eagerly...
I'm trying to restrict my NHibernate query with some basic date/time manipulation. More specifically, I want to execute the following statement (pseudo-SQL): select * from article where created_on + lifespan >= sysdate with: created_on is mapped to a property of type DateTime. lifespan is mapped to a property of type TimeSpan. sysda...
Is it possible to get NHibernate to generate a query similar to the following with HQL or Criteria API? select * from ( select row_number() over ( partition by Column1 order by Column2 ) as RowNumber, T.* from MyTable T ) where RowNumber = 1 I can get it to execute the inner select using the formu...
The Car entity is mapped to a database table with 2 columns: ID and Color. CarDao has the following method: Map<Color, Integer> countByColor(); If we have 3 red cars and 2 blue cars in the database table, the method returns a map with 2 keys (red and blue) and the corresponding count (3 resp. 2). I would like to do this with the Cri...
I have the following mapping files: <?xml version="1.0" encoding="utf-8"?> <hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="MyAssembly" namespace="EntityNamespace"> <class name="Server" xmlns="urn:nhibernate-mapping-2.2" table="tblServer" > <id name="Id" type="int"> <generator class="native"...
I'm trying to pull back a list of items that have a specific type of item in a set. For example: <class name="Owner" table="OWNER"> <id name="id" column="OWNER_ID" /> <set name="cats" table="OWNER_CATS" lazy="false"> <key column="OWNER_ID" /> <many-to-many class="Cat" /> </set> <class name="Cat" table="CAT" discriminator-v...