Nestjs中具有TypeORM的重复列名称

Question

我们有两个实体：EstateIntegrationEntity和EstateEntity

当我们尝试在estateIntegrationRepository上使用.findOne时，我们得到以下错误：

[Nest] 5537   - 10/01/2020, 8:37:55 AM
[ExceptionsHandler] ER_DUP_FIELDNAME: Duplicate column name 'EstateIntegrationEntity_estate_id' +1590ms
QueryFailedError: ER_DUP_FIELDNAME: Duplicate column name 'EstateIntegrationEntity_estate_id'
    at ...

我们创建了一个从EstateIntegrationEntity到EstateEntity的OneToOne关系。

import { EstateEntity } from "src/estates/estate.entity";
import { Column, Entity, JoinColumn, OneToOne, PrimaryGeneratedColumn, RelationId } from "typeorm";

@Entity({ name: 'estate_integrations' })
export class EstateIntegrationEntity {
  @PrimaryGeneratedColumn()
  id: number;

  @RelationId((estateIntegrationEntity: EstateIntegrationEntity) => estateIntegrationEntity.estate)
  estate_id: number;

  @OneToOne(() => EstateEntity, { eager: true })
  @JoinColumn({ name: 'estate_id' })
  estate: EstateEntity;

  ...
}

以及从EstateEntity到EstateIntegrationEntity的关系：

import { EstateIntegrationEntity } from 'src/integrations/estate.integration.entity';
import { Column, Entity, JoinColumn, ManyToOne, OneToOne, PrimaryGeneratedColumn } from 'typeorm';

@Entity('estates')
export class EstateEntity {
  @PrimaryGeneratedColumn()
  id: number;

  @Column('varchar' || null)
  uuid: string;

  @OneToOne(
    () => EstateIntegrationEntity,
    estate_integration => estate_integration.estate,
  )
  estate_integration: EstateIntegrationEntity;
}

此错误仅发生在.findOne()上，而不会出现在.find()上

async findEstateById(id: string): Promise<EstateIntegrationEntity> {
  return await this.estateIntegrationRepository.findOne({
    where: {
      external_id: id
    }
  });
}

Answer 1

您可以更改字段的名称。我刚刚遇到了一个类似的错误，并用@Column({ name：'name_the_fields_with_different_name‘})修改了它。因为问题是，如果在表中具有相同的名称，则find必须具有相同名称的to字段。

Answer 2

对于这种情况，您有3种解决方案：

1-将列名从'estate_id‘更改为其他名称，如'id_estate’

2-使用TypeORM编写自定义连接语句

3-我最喜欢的解决方案是使用这样的命名策略：

• 首先输入install npm i --save typeorm-naming-strategies，然后在您的typeorm配置文件中输入

const SnakeNamingStrategy = require('typeorm-naming-strategies')
  .SnakeNamingStrategy;
   module.exports = {
        name: 'name',
        type: 'mysql',
        host: 'localhost',
        port: 3306,
       ...
       namingStrategy: new SnakeNamingStrategy(),
    }