orm - How to implement one-to-many relationship with join table using sequelize-npm in node.js -

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i writing rest apis in node.js sequelize mysql orm. know, how achieve n:m relationship between 2 tables using sequelize association. defined here in official documentation of sequelize.

i want achieve one-to-many relationship using join table.

my approach achieve :

parent.model.js

module.exports = function(sequelize, datatypes){     var parent = sequelize.define('parent', {                 parent_id:{                     type:datatypes.integer,                     field:'parent_id',                     primarykey: true,                     autoincrement: true,                     unique:true                 },                 parent_name:{                     type: datatypes.string,                     field: 'parent_name'                 },         },         {             classmethods:{                 associate:function(models){                     parent.belongstomany(models.child, {                         through:'parent_child_mapping',                         foreignkey:'parent_id'                     });                 }             }         }     );     return parent; }

child.model.js

module.exports = function(sequelize, datatypes){     var child = sequelize.define('child', {                 child_id:{                     type:datatypes.integer,                     field:'child_id',                     primarykey: true,                     autoincrement: true,                     unique:true                 },                 child_name:{                     type: datatypes.string,                     field: 'child_name'                 },         },         {             classmethods:{                 associate:function(models){                     child.belongsto(models.parent, {                         through:'parent_child_mapping',                         foreignkey:'child_id'                     })                 }             }         }     );     return child; }

after syncing new table structure follows :

enter image description here

my problem:

  • why sequelize creating foreign key childchildid ?
  • will work ?

in parent.model.js should write 

parent.hasmany

instead of 

parent.belongstomany

if write "belongstomany" creates n:m relation described in here http://docs.sequelizejs.com/en/latest/api/associations/belongs-to-many/

edit: here doc "hasmany" : http://docs.sequelizejs.com/en/latest/api/associations/has-many/


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