Mysql 当一个表中的一列引用另一个表中的三列时，如何连接两个表？

我有两个表，分别是User和User_activity，它们的结构是

用户

id 
name
email
etc..

用户活动

id,
initiator_id,
source_id,
target_id,
activity_code,
activity

在这里，我想选择一个用户的所有活动列表（我可以将它们引用到source_id），其中包含启动器、源、目标的所有名称

---

如何实现这一点？

您只需加入三次，在引用用户的三次过程中为每个f使用别名

SELECT sourceUser.name, targetUser.name, initiatorUser.name FROM user_activity
INNER JOIN User as sourceUser on sourceUser.id = user_activity.source_id
INNER JOIN User as targetUser on targetUser.id = user_activity.target_id
INNER JOIN User as initiatorUser on initiatorUser.id = user_activity.initiator_id
WHERE source_id = MyUserIdQueryValue

SELECT
  user_activity.*,
  Initiator.Name   AS InitiatorName,
  Source.Name      AS SourceName,
  Target.Name      AS TargetName
FROM
  user_activity
INNER JOIN
  user             AS Initiator
    ON Initiator.ID = user_activity.initiator_id
INNER JOIN
  user             AS Source
    ON Source.ID    = user_activity.source_id
INNER JOIN
  user             AS Target
    ON Target.ID    = user_activity.target_id

---

您只需加入三次，在三次引用用户时为每个f使用别名

SELECT
  user_activity.*,
  Initiator.Name   AS InitiatorName,
  Source.Name      AS SourceName,
  Target.Name      AS TargetName
FROM
  user_activity
INNER JOIN
  user             AS Initiator
    ON Initiator.ID = user_activity.initiator_id
INNER JOIN
  user             AS Source
    ON Source.ID    = user_activity.source_id
INNER JOIN
  user             AS Target
    ON Target.ID    = user_activity.target_id

---

请下层选民详细说明原因，以便我能够解决您的担忧？请下层选民详细说明原因，以便我能够解决您的担忧？