sqlize/hasOne 中的关系不起作用 [英] Relations in sqlize / hasOne does not work

问题描述

我正在尝试在商店表和产品之间建立 1:1 的关系.每个产品都应该有一个店铺表的外键，每个店铺都应该有一个产品的外键.

I am trying to create 1:1 relation between table of shops and product. Each product should have an foreign key of shop table and each shop should have foreign key of product.

我已经定义了这两个表.

i have defined those two tables.

module.exports = function( sequelize , DataTypes ){
    var shops = sequelize.define('shops',{
            id: {
                type: DataTypes.INTEGER,
                allowNull:false,
                primaryKey:true,
                autoIncrement:true
            },
            name:{
                type:DataTypes.STRING,
                allowNull:false
            },
            address:{
                type: DataTypes.STRING,
                allowNull:false
            },
            web:{
                type: DataTypes.STRING,
                allowNull:false
            },
            price:{
                type: DataTypes.INTEGER,
                allowNull:false
            }
    })
    return shops
}

`

var shop = require('./shops.js');

var shop = require('./shops.js');

module.exports = function( sequelize , DataTypes ){
    var component = sequelize.define('component',{
            id: {
                type: DataTypes.INTEGER,
                allowNull:false,
                primaryKey:true,
                autoIncrement:true
            },
            name:{
                type: DataTypes.STRING,
                allowNull:false
            },
            storage:{
                type: DataTypes.INTEGER,
                allowNull:false
            },
            bilance:{
                type: DataTypes.INTEGER,
                allowNull:false
            }
    },{
        classMethods:{
         associate:function(models){
          component.hasOne(shop,{foreignKey:'foreign_key'})
         }
        }
    })
    return component;
}

在 db.js 文件中使用一个连接它.

inside db.js file a connected it using.

db.shop.belongsTo(db.component)
db.component.hasOne( db.shop ,{foreignKey : 'shop_id'})

但是这添加了 componentId {foreign key} 和 shop_id 另一个外键，它们都添加到 shop 表中.

but this added componentId {foreign key} and shop_id another foreign key ,both of them to the shop table.

如果我替换 1:1 关系 if 1:n e.g

If i replace 1:1 relation if 1:n e.g

db.component.hasMany(..)

它做同样的事情，将两个外键添加到商店表中

It does the same thing , adds both foreign keys into the shops table

推荐答案

您需要从回调方法中提供给您的 models 对象中引用 shop.所以在这种情况下你会这样做:

You need to reference shop from the models object provided to you in the callback method. So in this case you'd do:

classMethods:{
    associate:function(models){
        component.hasOne(models.shop,{foreignKey:'component_shop_FK'})
    }
}

注意如果你想给FK添加一个约束(比如not null)，简单的添加allowNull: false.

Note if you want to add a constraint (such as not null) to the FK, simple add allowNull: false.

我相信您引用了错误的模型.您已经为商店对象列出了商店"，因此请尝试将 models.shop 更改为 models.shops！

I believe you're referencing the wrong model. You've listed 'shops' for your shop object, so try changing models.shop to models.shops!

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