TypeORM为什么我的关系列未定义?外键未定义 [英] TypeORM why is my relationship column undefined? foreign-key is undefined
问题描述
我只是使用TypeORM并发现关系列未定义
I just use TypeORM and find the relationship column is undefined
@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
之类的时候,
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,它是怎么做的?外键是否存在未定义?
I want to show organization id, how typeORM do it? Foreign-Key is present undefined?
推荐答案
您需要延迟加载关系,或者需要在查找中指定关系
You need to either lazy load the relation or you need to specify the relation in the find
惰性:
@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"]
})
您也可以总是进行急切的加载,但是我建议您不要这样做,因为那样一来,当它获取一个人时,它将始终执行连接.
You could also always do an eager load, but i'd advise against this since then it would always do the join when it fetches a person.
如果要查询 belong_organizationId
,则需要将其字段添加到 person
实体.此字段通常类似于 belongOrganizationId
If you want to query the belong_organizationId
you need to add its field to the person
entity. This field is usual something like belongOrganizationId
那会
@Entity({name: 'person'})
class Person {
...
@Column()
belongOrganizationId:number
@ManyToOne(() => Organization, org => org.people, { nullable: true})
belong_organization!: Organization;
...
}
这也可以查询其ID.
您还可以更直接地查询它,但这会给您留下一些非常丑陋且难以维护的代码:
You could also query it more directly but this leaves you with some pretty ugly and unmaintainable code:
const findOptions: {
where :{
id,
'belong_organization.id': belong_organizationId
}
}
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