问题描述
我只是使用TypeORM并发现关系列未定义
@Entity({name: 'person'})
export class Person {
@PrimaryGeneratedColumn('uuid')
id!: string;
@OnetoOne( () => User)
@JoinColumn()
user!: User;
@Column({
type: "enum",enum: PersonTitle,default: PersonTitle.Blank
})
title?: string;
@Column({type: 'varchar',default: ''})
first_name!: string;
@Column('varchar')
last_name!: string;
@ManyToOne(() => Organization,org => org.people,{ nullable: true})
belong_organization!: Organization;
我也有Organization
实体:
export class Organization {
@PrimaryGeneratedColumn('uuid')
id!: string;
...
}
当我使用Repository
时,
const db = await getDatabaseConnection()
const prep = db.getRepository<Person>('person')
presult = await prep.findOne({where: {id}})
console.log(result)
我的结果是:
Person {
id: '75c37eb9-1d88-4d0c-a927-1f9e3d909aef',user: undefined,title: 'Mr.',first_name: 'ss',last_name: 'ls',belong_organization: undefined,// I just want to kNow why is undefined? even I can find in database the column
expertise: [],introduction: 'input introduction',COVID_19: false,contact: undefined
}
数据库表如下:
"id" "title" "first_name" "last_name" "expertise" "COVID_19" "userId" "belongOrganizationId" "introduction"
"75c37eb9-1d88-4d0c-a927-1f9e3d909aef" "Mr." "test" "tester" "nothing" "0" "be426167-f471-4092-80dc-7aef67f13bac" "8fc50c9e-b598-483e-a00b-1d401c1b3d61" "input introduction"
我想显示组织ID,如何输入ORM?外键是否存在未定义?
解决方法
您需要延迟加载关系,或者需要在查找中指定关系
Lazy:
@Entity({name: 'person'})
class Person {
...
@ManyToOne(() => Organization,org => org.people,{ nullable: true})
belong_organization!: Organization;
...
}
...
async logOrganization() {
const db = await getDatabaseConnection()
const prep = db.getRepository<Person>('person')
presult = await prep.findOne({where: {id}})
console.log(await result.belong_organization)
}
const prep = db.getRepository<Person>('person')
presult = await prep.findOne({
where: { id },relations: ["belong_organization"]
})
您也可以始终进行急切的加载,但是我建议您不要这样做,因为那样以后它将在获取人时始终执行联接。
如果要查询belong_organizationId
,则需要将其字段添加到person
实体。该字段通常类似于belongOrganizationId
那会
@Entity({name: 'person'})
class Person {
...
@Column()
belongOrganizationId:number
@ManyToOne(() => Organization,{ nullable: true})
belong_organization!: Organization;
...
}
这也可以查询其ID。
您也可以直接查询它,但这会给您留下一些非常难看且难以维护的代码:
const findOptions: {
where :{
id,'belong_organization.id': belong_organizationId
}
}