many-to-many

问题 How do I read a many-to-many table via EF? I have no idea how to use the many-to-many table. Let's say Product_Category where it got ProductID and CategoryID . How can I access it trough e.g. using(Entities db = new Entities) { /* cant access these here.. */} method?? I can however reach Product_Category , but cant access its ProductID or CategoryID . I want to list every product e.g. where Product_Category.CategoryID == Category.ID . I have never used many-to-many tables before, so I

问题 I have gone through tons of questions about this issue here in Stackoverflow but I think this is different. What I'm trying to do is give user ability to filter posts by tags so that one sees only the tags that are left for filtering. In other words if user selects tag "tag1", it show posts with that tag and also show other tags that post shares but hide tags that no visible post have after filtering. I have tables posts , posts_tags and tags . Posts_tags have post_id and tag_id. I have

问题 The docs only show using a many-to-many-through/intermediary model where the model is in the same app. How can I do this with the intermediary table in a different app? I don't think from app import intermediary works, as the through attribute is declared within apostrophes. 回答1: Answer: Use 'app.model' . I didn't think it would work in this context, but it does 来源： https://stackoverflow.com/questions/31746235/django-1-8-how-do-i-use-a-model-in-a-different-app-as-a-through-in-a-many-to

问题 In database, I have following three tables, where User and Profile have many-to-many relationship and joined with User_Profile as follow: User User_Profile Profile ---- ------------ ------- user_id user_id profile_id user_name profile_id profile_description user_time Class UserHbm and ProfileHbm are used: @Entity @Table(name = "User") public class UserHbm { @Id @GeneratedValue(generator = "id-generator") @GenericGenerator(name = "id-generator", strategy = "com.xx.xxx.XXXSequenceGenerator",

问题 Okay, so I'm trying to create a relationship where users can follow other users or follow categories. I got a recommendation to use Polomorpic Many to Many relationships. Right now I'm trying to create a follower - followee relationship but I can't wrap my head around how to set up the models and the controller. TABLES Users Schema::create('users', function (Blueprint $table) { $table->increments('id'); $table->string('email'); $table->string('password'); $table->string('first_name'); });

问题 This is a long introduction for a short question, sorry!! I'm working with EF 4.3.1 Code First and I've got the following model public class Action { protected Action() { } public virtual int ActionID { get; protected set; } [Required] [StringLength(DataValidationConstants.NameLength)] public virtual string Name {get; set;} [StringLength(DataValidationConstants.DescriptionLength)] public virtual string Description { get; set; } public virtual ICollection<Role> Roles { get; set; } public

问题 I have 2 Entities User Article and a “likedByUsers” Many To Many relationship between both. When I show an article, I want to know if the user has liked it so a heart icon is shown. I've got this in the ArticleRepository: public function findOneBySlug($slug,$userId): ?Pack { return $this->createQueryBuilder('p') ->andWhere('p.slug = :val') ->setParameter('val', $slug) ->addSelect('COUNT(u) AS userLike', 'p') ->leftJoin("p.users", 'u', 'WITH', 'u.id = :userId') ->setParameter('userId', $userId

问题 I have 2 Entities User Article and a “likedByUsers” Many To Many relationship between both. When I show an article, I want to know if the user has liked it so a heart icon is shown. I've got this in the ArticleRepository: public function findOneBySlug($slug,$userId): ?Pack { return $this->createQueryBuilder('p') ->andWhere('p.slug = :val') ->setParameter('val', $slug) ->addSelect('COUNT(u) AS userLike', 'p') ->leftJoin("p.users", 'u', 'WITH', 'u.id = :userId') ->setParameter('userId', $userId

问题 I have a manytomany relationship between my user table and profile. So I created a entity UserProfile public class User implements Serializable { private static final long serialVersionUID = 1L; @Id private Integer id; private String email; @JsonBackReference @OneToMany(mappedBy = "user", cascade = CascadeType.ALL) private List<UserProfile> userProfiles = new ArrayList<UserProfile>(); public User() { } GETTER / SETTER } public class Profile implements Serializable { private static final long

问题 So i'm trying to use [Slauma's Answer][1] What i have done so far, Model ViewModelProspectUsers public int Id { get; set; } public string User { get; set; } public IEnumerable<ViewModelUserProspectSelect> Prospects { get; set; } Model ViewModelUserProspectSelect public int ProspectID { get; set; } public string Name { get; set; } public bool IsSelected { get; set; } View UserInProspect @model OG.ModelView.ViewModelProspectUsers @using (Html.BeginForm()) { <div class="container"> <div class=