criteria | 易学教程

NHIbernate OR Criteria Query

阅读更多关于 NHIbernate OR Criteria Query

I have the following mapped classes Trade { ID, AccountFrom, AccountTo } Account {ID, Company} Company {ID} Now I cannot figure out a way select all trades where AccountFrom.Company.ID = X OR AccountTo.Company.ID = X I can get AND to work using the following: criteria.CreateCriteria("AccountFrom").CreateCriteria("Company").Add(Restrictions.Eq("ID", X); criteria.CreateCriteria("AccountTo").CreateCriteria("Company").Add(Restrictions.Eq("ID", X); But how can I transform this into an OR rather an an AND. I have used Disjunction previously, but I cannot seem to know how to add separate criteria,

setResultTransformer in Criteria

阅读更多关于 setResultTransformer in Criteria

What is the use of setResultTransformer method in criteria API? Can someone explain this with a simple example? I read the javadocs but i am not able to understand them clearly. Regards, The default ResultTransformer for a Criteria query which does not use setProjections() will be ROOT_ENTITY . If we have Student in a ManyToMany relationship to Department a query might look like this ... Session session = (Session) getEntityManager().getDelegate(); Criteria crit = session.createCriteria(Student.class) .createAlias('departments', 'department'); This query will return duplicates. But set the

How to use hibernate criteria to return only one element of an object instead the entire object?

阅读更多关于 How to use hibernate criteria to return only one element of an object instead the entire object?

I'm trying to get only the list of id of object bob for example instead of the list of bob. It's ok with a HQL request, but I would know if it's possible using criteria ? An example : final StringBuilder hql = new StringBuilder(); hql.append( "select bob.id from " ) .append( bob.class.getName() ).append( " bob " ) .append( "where bob.id > 10"); final Query query = session.createQuery( hql.toString() ); return query.list(); I think you could do that with Projections, something like Criteria.forClass(bob.class.getName()) .add(Restrictions.gt("id", 10)) .setProjection(Projections.property("id"))

NHibernate 2.1: LEFT JOIN on SubQuery with Alias (ICriteria)

阅读更多关于 NHibernate 2.1: LEFT JOIN on SubQuery with Alias (ICriteria)

问题 I am basically trying to create this query with NHibernate ICriteria interface: SomeTable 1:n AnotherTable SomeTable has columns: PrimaryKey, NonAggregateColumn AnotherTable has columns: PrimaryKey, ForeignKey, AnotherNonAggregate, YetAnotherNonAggregate SELECT table1.NonAggregateColumn, subquery.SubQueryAggregate1, subquery.SubQueryAggregate2 FROM SomeTable AS table1 LEFT JOIN ( SELECT table2.ForeignKey, COUNT(table2.AnotherNonAggregate) AS SubQueryAggregate1, AVG(table2

jpa criteria for many to many relationship

阅读更多关于 jpa criteria for many to many relationship

I have 2 POJO classes in Java, Answer and Collaborator, in a many-to-many relationship. class Answer { @ManyToMany(cascade = CascadeType.ALL) @JoinTable(name = "ANSWERS_COLLABORATORS", joinColumns = { @JoinColumn(name = "aid") }, inverseJoinColumns = { @JoinColumn(name = "cid") }) private Set<Collaborator> collaborators = new HashSet<Collaborator>(0); } Class Answer has a set of Collaborator , but a Collaborator doesn't keep a set of Answer . What I need to do from Hibernate CriteriaQuery is to find the collaborators for an answer given by id. I have already done this with Hibernate Criteria (

Grails/Hibernate: how to order by isnull(property) to get NULLs last?

阅读更多关于 Grails/Hibernate: how to order by isnull(property) to get NULLs last?

问题 Normally when ordering ascending by a field, you get the NULL values first, and then the more interesting values. Often, you want NULL values last. In MySQL, you can do this with: SELECT * FROM people ORDER BY ISNULL(name), name; However, I'm using Grails with Hibernate criteria, and I have absolutely no idea how to do this there. Is this even supported in any way? Is there some way to order by a custom SQL expression? I'd hate to rewrite all my criteria to plain SQL just to get it to sort

Grails: Projection on many tables?

阅读更多关于 Grails: Projection on many tables?

问题 I have some problems with projection in Grails. Could you please help me review them and suggest solutions for me? I want to query data on many tables which has many-to-one relationship and projection on some properties on both of them. For example: class Person { int id String name String address static hasMany = [cars : Car] } class Car { int id String brand long price Person owner static belongsTo = [owner : Person] } So, how can I use just one query withCriteria (apply projection) to get

Doctrine 2.3 Criteria. Accessing a related Object

阅读更多关于 Doctrine 2.3 Criteria. Accessing a related Object

问题 I am trying to set up a Criteria according to the Doctrine Docs. Unfortunately they don't tell you how to access attributes of an related Object. Let me give you an example. I have an ArrayCollection of Products. Every Product has a Category. I want to filter the ArrayCollection for a Category Name. Now I am trying to set up a Criteria as follows: $criteria = Criteria::create() ->where(Criteria::expr()->eq("category.name", "SomeCategoryName")); Now I get the following Exception: An exception

Hibernate criteria query with subquery joining two columns

阅读更多关于 Hibernate criteria query with subquery joining two columns

问题 I have a table, "Quote", mapped in hibernate that has a composite key of an integer id and a date, and several additional columns. I'd like to write a criteria query that uses a DetachedCriteria to get the row for each id with the greatest date. In sql, I might write a query like SELECT * FROM Quote q1 INNER JOIN (SELECT id, max(date) as maxdate FROM Quote GROUP BY id, date) q2 ON q1.id = q2.id AND q1.date = q2.maxdate In hibernate, I think can create a DetachedCriteria for the "group by"

Hibernate Criteria Order By

阅读更多关于 Hibernate Criteria Order By

问题 I have a table called Gift, which has a one-to-many relationship to a table called ClickThrough - which indicates how many times that particular Gift has been clicked. I need to query for all of the Gift objects, ordered by ClickThrough count. I do not need the ClickThrough count returned, as I don't need anything done with it, I just want to use it for purposes of ordering. I need the query to return a List of Gift objects directly, just ordered by ClickThrough count. How do I do this using