“无法读取未定义的属性'tablePath‘”(类型为ORM )

Question

    {
        "name": "TypeError"
"message": "Cannot read property 'tablePath' of undefined",
        "stack": "TypeError: Cannot read property 'tablePath' of undefined\n    at C:\\working\\Hianfa\\Hianfa\\api\\src\\query-builder\\SelectQueryBuilder.ts:1500:76\n    at Array.map (<anonymous>)\n    at SelectQueryBuilder.createJoinExpression (C:\\working\\Hianfa\\Hianfa\\api\\src\\query-builder\\SelectQueryBuilder.ts:1462:57)\n    at SelectQueryBuilder.getQuery (C:\\working\\Hianfa\\Hianfa\\api\\src\\query-builder\\SelectQueryBuilder.ts:54:21)\n    at SelectQueryBuilder.QueryBuilder.getQueryAndParameters (C:\\working\\Hianfa\\Hianfa\\api\\src\\query-builder\\QueryBuilder.ts:392:28)\n    at SelectQueryBuilder.<anonymous> (C:\\working\\Hianfa\\Hianfa\\api\\src\\query-builder\\SelectQueryBuilder.ts:1948:40)\n    at step (C:\\working\\Hianfa\\Hianfa\\api\\node_modules\\tslib\\tslib.js:136:27)\n    at Object.next (C:\\working\\Hianfa\\Hianfa\\api\\node_modules\\tslib\\tslib.js:117:57)\n    at C:\\working\\Hianfa\\Hianfa\\api\\node_modules\\tslib\\tslib.js:110:75\n    at new Promise (<anonymous>)"
    }

在尝试使用映射表映射两个表时，我遇到了这个错误。

供应商模型(表1)

@ManyToMany(type => VendorToCategory, vendorToCategory => vendorToCategory.vendor)
// @JoinColumn({name: 'vendor_vendor_category_id'})
public vendorToCategory: VendorToCategory[];

供应商类别模型(表2)

 @ManyToMany(type => VendorToCategory, vendorToCategory => vendorToCategory.vendorCategory)
    @JoinColumn({name: 'vendor_vendor_category_id'})
    public vendorToCategory: VendorToCategory[];

映射表(供应商到类别)

   @ManyToMany(type => Vendor, vendor => vendor.vendorToCategory)
    @JoinColumn({ name: 'vendor_id' })
    public vendor: Vendor[];

@ManyToMany(type => VendorCategory, vendorCategory => vendorCategory.vendorToCategory)
@JoinColumn({ name: 'vendor_category_id' })
public vendorCategory: VendorCategory[];

请帮我解决这个错误！

Answer 1

您的问题与@JoinColumn装饰器的错误使用有关；您应该在处理@ManyToMany关系时使用@JoinTable。

因此，不是这样：

@ManyToMany(type => VendorToCategory, vendorToCategory => 
vendorToCategory.vendorCategory)
@JoinColumn({name: 'vendor_vendor_category_id'})
public vendorToCategory: VendorToCategory[];`

你应该这样写：

@ManyToMany(type => VendorToCategory, vendorToCategory => vendorToCategory.vendorCategory)
@JoinTable({
   name: "vendor_vendor_category_id",
   joinColumn: {
    name: "vendorCategory",
    referencedColumnName: "id"
   },
   inverseJoinColumn: {
    name: "vendor",
    referencedColumnName: "id"
    }})
public vendor: Vendor[];`

当涉及到处理关系时，TypeORM文档并不那么具体，但它们确实提供了一些有用的示例。所以，如果你想要一个详细的答案，可以看看them。