MYSQL - 其中ID多次出现在列名的显示列表

Question

任何人都可以指出什么是错用下面的代码，请

---与正确答案EDITED ---

SELECT hist.TutorID, FirstName, LastName, COUNT(hist.TutorID) as 
number_students 
FROM match_history as hist 
JOIN tutor ON tutor.TutorID 
WHERE hist.TutorID = tutor.TutorID 
GROUP BY hist.TutorID 
HAVING (number_students > 1) 

Answer 1

添加“分组依据”你的子查询，并在where子句：

SELECT tut.TutorID, FirstName, LastName 
FROM tutor AS tut 
WHERE tutorid in (SELECT TutorID FROM match_history group by tutorid HAVING COUNT(TutorID) >1); 

。希望名字和来自老师的桌子姓氏。或者提供你的表格结构。

Answer 2

SELECT tut.TutorID, FirstName, LastName 
FROM tutor AS tut, match_history as hist 
WHERE tut.TutorID in (SELECT TutorID FROM match_history GROUP BY TutorID HAVING COUNT(TutorID) > 1); 

内选择提供了具有一个计数> 1 TutorIDs的列表，外部只从由内选择设置ID的列表中选择抓斗id和其他列。

Answer 3

SELECT tut.TutorID, 
FirstName, 
LastName 
FROM tutor AS tut 
LEFT JOIN match_history hist ON (tut.TutorID = hist.TutorID) 
GROUP BY tut.TutorID 
HAVING COUNT(hist.TutorID) > 1 

Answer 4

使用GROUP BY条款：

SELECT tut.TutorID, FirstName, LastNamecode 
FROM tutor AS tut, match_history as hist 
WHERE tut.TutorID in (SELECT TutorID FROM match_history 
GROUP BY TutorID 
HAVING COUNT(TutorID) > 1);