我正在尝试连接同一个表"travel_plan“两次,因为我需要的值是location_from & location_to,然后我可以将该值连接到我的cities表中,以获取城市名称。SELECT * FROM travel_plan LEFTJOIN Cities ON Cities.CityID = travel_plan.location_from AS
我想要两个execute同时查询,但是我得到了mysql_error。LT.PLesTypName, L.LesMinMark left joinLessonTypes LT on (L.LesTypCode=LT.LesTypCode)
left join EducationalSections ES on (L.EduSecCodeError description: You have an
我有一个MySQL查询,需要两次left join。有四个表A、B、C、D和两种可能性,如果A.label为null,left join B on B.name=A.name否则,如果A.label不为null,则left join C on C.name=A.name
left join D on C.cid=D.id;