如何在续集中建模一对多关联？

Question

I'm new to Sequelize, and I'm trying to figure out, how should I model one-to-many relationship.

My problem is as follows: one term, many papers.

var Term = sequelize.define( 'Term', ... );
var Paper = sequelize.define( 'Paper', ... );

Let's assume I have a term. Each term can have many papers, and I'd like to add/remove papers for my term. I'd also like to get all the papers for the term.

var term;
...
term.getPapers( ... );
term.setPapers( ... );
term.addPaper( paper );
term.removePaper( paper );

Now, let's assume I have a paper. I'd like to get/set the term for my paper.

var paper;

...

paper.getTerm();
paper.setTerm();

How can it be achieved using sequelize? I've been studying docs for hours, and also looking for some glues in the net, but without any results. I find this kind of association very poorly documented in sequelize (one-to-one and many-to-many are way better).

Update :

All right, several hours later I worked out how it works:

Term.hasMany( Paper, { as: 'papers' } );
Paper.hasOne( Term );

Now we can do:

term.addPaper( paper );
term.removePaper( paper );

paper.getTerm()
  .success( function( term )
  {
    ...
  });
paper.setTerm( term );

I've got used to Django, and it seems that Sequelize is FAR less mature, both in terms of code and documentation...

Answer 1

First you have to create the association. You did it correctly:

  Term.hasMany( Paper, { as: 'papers' } );
  Paper.hasOne( Term );

Then you have to sync this declarations:

  sequelize.sync();

And now persist data. You need to save the objects before to associate it.

  term.create()...
  paper1.create()...
  paper2.create()...

  term.setPapers([paper1, paper2]).success(function() {
     // saved!
  })

Reference: http://docs.sequelizejs.com/en/1.7.0/docs/associations/#many-to-many-associations

Answer 2

这取决于你如何构建数据库，这会想到..

paper.hasOne(term,{as:"PaperTerm"})

Answer 3

Well that's great that you had figured out how it works but it would have been correct if you had used Paper.belongsTo(Term); instead of Paper.hasOne( Term ); Here is the reference if you'd like to read more about