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Sequelize 自引用多对多; 如何指定我加入的内容

[英]Sequelize self-referential many-to-many; how to specify what I'm joining on

I have a Sequelize structure that associates my User table to itself through a Follow table, with follower and following .我有一个 Sequelize 结构,它通过Follow表将我的User表与自身关联,并带有followerfollowing I'm 99% certain that I have all of the necessary pieces for this to be working the way I expect it to;我有 99% 的把握,我拥有所有必要的部件,可以按照我期望的方式工作; I've the aliased我有别名

User.belongsToMany(models.User, { through: models.Follow, as: 'Followers', foreignKey: 'follower'});
User.belongsToMany(models.User, { through: models.Follow, as: 'Following', foreignKey: 'following'});

as well as

User.hasMany(models.Follow, { foreignKey: 'following' });
User.hasMany(models.Follow, { foreignKey: 'follower' });

and

Follow.belongsTo(models.User, { foreignKey: 'following', as: 'Following' });
Follow.belongsTo(models.User, { foreignKey: 'follower', as: 'Follower' });

And I'm able to call我可以打电话

User.findByPk(id, {
  include: {
    model: Follow
  }
});

which returns a single user and an array of Follow entries.它返回一个用户和一个 Follow 条目数组。
The problem I'm having is, Sequelize seems to be defaulting to creating the Follow query as where: { followING: User.id } rather than where: followER , such that if I have 1 user FOLLOWING themselves and 2 other people, but only FOLLOWED BY themselves, it only returns 1 result from my Follow table.我遇到的问题是,Sequelize 似乎默认创建Follow查询为where: { followING: User.id }而不是where: followER ,这样如果我有 1 个用户 FOLLOWING 自己和 2 个其他人,但只有FOLLOWED BY 他们自己,它只从我的 Follow 表中返回 1 个结果。 As I was cycling through the primary keys for the handful of users in my seed, only the following value in my results change, such that I'm only ever returning a users' followers, not the other users that user is following.当我在我的种子中为少数用户循环访问主键时,我的结果中只有following值会发生变化,这样我只会返回用户的关注者,而不是用户关注的其他用户。
Is there a way to specify in an include which specific column I'm trying to join on, when multiple columns match the Sequelize object to which I'm joining?当多个列与我要加入的 Sequelize object 匹配时,有没有办法在include我尝试加入的特定列中指定?
I understand that worst case scenario I can always skip the User step and go straight to我知道最坏的情况我总是可以跳过User步骤和 go 直接到

Follow.findAll({
  where: {
    follower: id
  }
})

But that restricts my immediate access to the User object and I'd have to write an additional query, which seems cumbersome considering a self-associated many-to-many capability exists.但这限制了我对用户 object 的立即访问,我必须编写一个额外的查询,考虑到存在自关联的多对多功能,这似乎很麻烦。

If you wish to get a user with followers or with following users you don't need to indicate Follow table.如果您希望获得具有关注者或关注用户的用户,则无需指明Follow表。 All you need is to indicate an alias of a required association:您只需要指明所需关联的别名:

User.findByPk(id, {
  include: {
    model: User,
    as: 'Followers'
  }
});
User.findByPk(id, {
  include: {
    model: User,
    as: 'Following'
  }
});

In case you need to include Follow directly you need to add an associations like this:如果您需要直接包含Follow ,则需要添加如下关联:

User.hasMany(models.Follow, { as: 'FollowerLinks', foreignKey: 'follower'});
User.hasMany(models.Follow, { as: 'FollowingLinks', foreignKey: 'following'});

And you also should indicate an alias so that way Sequelize will know what association to use:您还应该指定一个别名,以便 Sequelize 知道要使用什么关联:

User.findByPk(id, {
  include: {
    model: Follow,
    as: 'FollowerLinks'
  }
});

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