Question

我自己有多种型号：

用户（id，用户名）

团队（身份证，姓名）

技能（身份证，姓名）

TeamSkill（id，skill_id，team_id）

TeamSkillUpvote（id，team_skill_id，user_id）

我想提出这样的问题：

select team.id, team.name, team_skill_upvotes.user_id
from skill, team_skills, team
where skill.id = <THE_ID_OF_MY_MODEL>
and skill.id = team_skills.skill_id
and team_skills.team_id = team.id
and team_skills.id = team_skill_upvotes.team_skill_id

任何人都可以提供帮助吗？

谢谢！

Answer 1

搜索后我找到了答案......它只需几步即可完成：

1：定义TeamSkill的关系：

export interface ITeamSkillRelations {
  team: Team;
  upvotes: Collection<TeamSkillUpvote>;
}

export class TeamSkill extends bookshelf.Model<TeamSkill>{
  ...
  public relations: ITeamSkillRelations;

  public upvotes(): Collection<TeamSkillUpvote> {
    return this.hasMany(TeamSkillUpvote, TeamSkillUpvote.teamSkillIdAttribute/*team_skill_id*/);
  }

  public team(): Team {
    return this.belongsTo(Team, TeamSkill.teamIdAttribute/*team_id*/);
  }
  ...
}

2：神奇：

export class Skill extends bookshelf.Model<Skill> {
  public getTeams(): Promise<ITeamOfASkill[]> {
    var fetchOptions: CollectionFetchOptions = {
      withRelated: [
        TeamSkill.relatedTeamSkillUpvotesAttribute/*upvotes*/,
        TeamSkill.relatedTeamAttribute/*team*/
      ]
    };

    return this.teamSkills()
      .fetch(fetchOptions)
      .then((teamSkillsCollection: Collection<TeamSkill>) => {
        var teamSkills: TeamSkill[] = teamSkillsCollection.toArray();

        return _.map(teamSkills, _skill => this._convertTeamSkillToTeamOfASkill(_skill));
      });
  }

  private _convertTeamSkillToTeamOfASkill(teamSkill: TeamSkill): ITeamOfASkill {
    var team: Team = teamSkill.relations.team;

    var upvotesCollection: Collection<TeamSkillUpvote> = teamSkill.relations.upvotes;
    var upvotes: TeamSkillUpvote[] = upvotesCollection.toArray();

    var upvotingIds =
      _.map(upvotes, _ => _.attributes.user_id);

    return {
      team: team,
      upvotingUserIds: upvotingIds
    };
  }
}

Bookshelf.js连接多个表

1 个答案: