We use @OneToMany for our Parent->Child->Child->Child DB relationship: @OneToMany(cascade = CascadeType.ALL) @JoinColumn(name = "THE_ID", nullable = false ) private List<ChildClass> children = new ArrayList<ChildClass>(); We have a scenario with a lot of data (100K inserts) where the performance is atrocious (actually times out) when ...
When querying into child collections should I be wary of performance and duplicate results which result from the use of CreateAlias("ChildCollectionName", "alias") would you think it would be better to just perform subqueries on Child Collections to get a big list of "parentId"s and then do an In clause on the parent. For Example clas...
Hi, I' ve got 2 tables... Challenge and ChallengeYear, ChallengeYear is only to create a list of years in challenge. I only want to make Challenge an entity, containing a list of List years. Is this possible? I've looked in to @SecondaryTable together with @JoinColumn and @OneToMany, but neither of those can do the trick, or i am ove...
hello, I have a one to many relationship and when I try to delete a parent that haves more than one child the berforeInsert event gets called on the frst child. I have some code in this event that I mean to call before inserting a child, not when i'm deleting the parent! any ideas on what might be wrong? the entities: class MenuItem {...
I have this DB design: CREATE TABLE report ( ID MEDIUMINT PRIMARY KEY NOT NULL AUTO_INCREMENT, user MEDIUMINT NOT NULL, created TIMESTAMP NOT NULL, state INT NOT NULL, FOREIGN KEY (user) REFERENCES user(ID) ON UPDATE CASCADE ON DELETE CASCADE ); CREATE TABLE reportProperties ( ID ...
Hi I have two classes which have a Unidirectional One to Many relation with each other. public class Offer{ ... @OneToMany(cascade=CascadeType.ALL) @JoinTable(name = "Offer_Fields", joinColumns = @JoinColumn(name = "OFFER_ID"), inverseJoinColumns = @JoinColumn(name = "FIELDMAPPER_ID")) private Set<FieldM...
I have 2 entities/tables. One is a proper entity, let's call it data. It has a number of fields containing so-called "multilingual codes". The second table, code, contains the multilingual values themselves. Here is some example data : Data table id name continentCode countryCode ------------------------------------ 1 ...
I am facing a problem due to that i'm newbie to grails i'm doing a website for reading stories and my goal now is to do save the content of the story into several pages to get a list and then paginate it easily .. so i did the following. in the domain i created two domains one called story and have this : class Story { String title ...
I have Hibernate Objects defined as Class SomeText{ private Long textId; private Set<Tag> Tags = new HashSet<Tag>(); @ManyToMany(cascade={CascadeType.PERSIST,CascadeType.MERGE }) @JoinTable(name = "text_tag_reln", joinColumns = { @JoinColumn(name = "textId") }, inverseJoinColumns = { @JoinColumn(name = "tagId") }) pu...
As per hibernate documentation: To map a bidirectional one to many, with the one-to-many side as the owning side, you have to remove the mappedBy element and set the many to one @JoinColumn as insertable and updatable to false. This solution is not optimized and will produce some additional UPDATE statements. @Entity public class...
Hi guys, I've got a table Category and a table TranslatableText. The category is like this create table Category ( id int not null, parent_id int default 0, TranslatableDescriptionId int default 1, primary key(id)); create table TranslatableText ( id int not null, lang enum ('NO','EN','FR'), text mediumtext, primary ke...
Hello there, I have those 2 tables Teacher and Contact, a teacher can have x Contacts SO here we are looking at a @OneToMany association. Tables Structure: User [userid, username, email,...] Contact [contactid, contactname, ref, reftype,...] I want to load from my User Class all the User's contacts. To do that I would do a query lik...