我可以按另一個表中的記錄數對SQL查詢結果進行排序嗎？

Question

事情是這樣的：

SELECT count(Answers.ID) as answertotal, Questions.* 
FROM Questions 
LEFT JOIN Answers ON Answers.qid=Questions.ID 
ORDER BY answertotal 

我使用SQLite，但任何例子應該有所幫助。

Answer 1

在MySQL中，這會工作：

SELECT count(Answers.ID) as answertotal, Questions.* 
FROM Questions 
LEFT JOIN Answers ON Answers.qid=Questions.ID 
GROUP BY Questions.ID 
ORDER BY answertotal 

在SQLLite，您可能需要添加額外的一層是這樣的：

SELECT q.*, tots.answertotal 
FROM Questions q 
INNER JOIN ( 
    SELECT count(Answers.ID) as answertotal, Questions.ID as questionid 
    FROM Questions 
    LEFT JOIN Answers ON Answers.qid=Questions.ID 
    GROUP BY Questions.ID 
) tots ON tots.questionid = q.ID 
ORDER BY tots.answertotal