链接一个Sequelize模型到两个不同的领域，从另一个模型

Question

我有两个型号：

• BusinessEntity和
• Invoice

我想Invoice有一个seller和buyer，两者都指向BusinessEntity记录。所以，我希望在invoices表（Invoice型号）有两个字段：seller_id和buyer_id。

所以，我做了这样的事情：

BusinessEntity

const BusinessEntity = sequelize.define("business_entity", { 
    display_name: Sequelize.STRING 
}); 

Invoice

const Invoice = sequelize.define("invoice", { 
    series: Sequelize.STRING, 
    number: Sequelize.INTEGER, 
    ... 
}); 

// Indeed, this creates the seller_id and buyer_id fields in the invoice 
Invoice.belongsTo(BusinessEntity, { as: "seller" }); 
Invoice.belongsTo(BusinessEntity, { as: "buyer" }); 

似乎不自然的我打电话给Invoice.belongsTo(BusinessEntity)，但如果我这样做：

BusinessEntity.belongsTo(Invoice, { as: "seller" }); 
BusinessEntity.belongsTo(Invoice, { as: "buyer" }); 

... seller_id和buyer_id列根本不创建。为什么？

---

我成功插入的发票，从business_entities表assiging IDS。

我该如何查询Invoice当我想includeseller和buyer在输出？

我想：

Invoice.findOne({ include: [BusinessEntity] }) 

但是失败，此错误：

business_entity is not associated to invoice! 

什么是做到这一点的正确方法？如何解决问题？

Answer 1

当您执行findOne查询时：Invoice.findOne({ include: [BusinessEntity] })还必须提及别名。

所以，你需要查询的格式如下：