如何使Loopback4中的模型在其模式中具有唯一的值？

import {Entity, model, property} from '@loopback/repository';

@model()
export class User extends Entity {
  @property({
    type: 'string',
    id: true,
    generated: true,
  })
  id: string;

  @property({
    type: 'string',
    required: true,
    unique: true, // 添加unique属性
  })
  email: string;

  // 其他属性和方法...
}

import {MigrationInterface, QueryRunner} from 'typeorm';

export class AddUniqueConstraintToUserEmail1621234567890 implements MigrationInterface {
  async up(queryRunner: QueryRunner): Promise<void> {
    await queryRunner.query(`
      ALTER TABLE "user"
      ADD CONSTRAINT "unique_email" UNIQUE ("email")
    `);
  }

  async down(queryRunner: QueryRunner): Promise<void> {
    await queryRunner.query(`
      ALTER TABLE "user"
      DROP CONSTRAINT "unique_email"
    `);
  }
}

lb-migration migrate