typeorm：如何进行 RIGHT JOIN 和 SELECT答案

【问题标题】：typeorm: How to do a RIGHT JOIN and SELECTtypeorm：如何进行 RIGHT JOIN 和 SELECT
【发布时间】：2017-08-15 09:31:10
【问题描述】：

请问如何使用 typeorm 进行以下查询

SELECT *
FROM "UserStrength"
RIGHT JOIN "Strength" ON "Strength"."id" = "UserStrength"."strengthId"

UserStrengthEntity 定义为：

@Entity("UserStrength")
export class UserStrengthEntity extends BaseEntity implements IUserStrength {
    @Column({default: false}) isCompleted: boolean;

    @ManyToOne(type => UserEntity, user => user.userStrengthArray, {
        cascadeAll: true
    })
    @JoinColumn({name: "userId"})
    user: UserEntity;

    @OneToMany(type => UserStrengthItemEntity, userStrengthItem => userStrengthItem.userStrength, {
        cascadeInsert: true,
        cascadeUpdate: true
    })
    userStrengthItemArray?: UserStrengthItemEntity[];

    @ManyToOne(type => StrengthEntity, strength => strength.userStrengthArray, {
        cascadeAll: true
    })
    @JoinColumn({name: "strengthId"})
    strength: StrengthEntity;
}

StrengthEntity 是：

@Entity("Strength")
export class StrengthEntity extends BaseEntity implements IStrength {
    @Column({length: 50}) name: string;
    @Column({length: 100}) title: string;
    @Column() strengthType: StrengthType;
    @Column({length: 10, nullable: true}) titleColor: string;
    @Column({nullable: true}) titleIcon: string;

    @ManyToOne(type => ClientEntity, clientEntity => clientEntity.strengthArray, {
        cascadeAll: true
    })
    @JoinColumn({name: "clientId"}) client: ClientEntity

    @OneToMany(type => StrengthItemEntity, strengthItem => strengthItem.strength, {
        cascadeInsert: true,
        cascadeUpdate: true
    })
    strengthItemArray: StrengthItemEntity[];

    @OneToMany(type => UserStrengthEntity, userStrength => userStrength.strength, {
        cascadeInsert: true,
        cascadeUpdate: true
    })
    userStrengthArray: UserStrengthEntity[];
}

我想加载一个 UserStrength，它可能与给定strengthType 的强度一起存在也可能不存在（我还需要对 UserEntity 进行 RIGHT JOIN 以进一步按 UserEntity.id 过滤）

谁能解释一下这是如何用 typeorm 完成的？

【问题讨论】：

标签： postgresql typescript right-join typeorm

【解决方案1】：

目前Typeorm中没有右连接，最好从反面建立关系并做左连接

【讨论】：