MySQL запрос, показывающий ошибку: # 1241 - операнд должен содержать 1 столбца

Question

Mysql-запрос,

SELECT qcat.name,
COUNT( CASE WHEN qas.state = "todo" THEN 1 END ) AS gtotal,
COUNT( CASE WHEN qas.state = "gradedright" THEN 1 END ) AS rightanswer, 
COUNT( CASE WHEN qas.state = "gradedwrong" THEN 1 END ) AS wronganswer, 
SUM(qas.fraction) AS grade,
quiza.id 
FROM mdl_quiz_attempts quiza
JOIN mdl_question_attempts qa ON qa.questionusageid = quiza.uniqueid 
JOIN mdl_question_attempt_steps qas ON qas.questionattemptid = qa.id 
JOIN mdl_question qstn ON ( qa.`questionid` = qstn.id ) 
JOIN mdl_question_categories qcat ON ( qstn.`category` = qcat.id ) 
WHERE quiza.id=1173 and FIND_IN_SET(qstn.id, (1,2,3,4,5,6)) GROUP BY quiza.id,qcat.name

с ошибкой: # 1241 - операнд должен содержать 1 столбец (ов)

Answer 1

Это неправильно:

FIND_IN_SET(qstn.id, (1,2,3,4,5,6))

Должно быть:

qstn.id IN (1,2,3,4,5,6)

или

qstn.id BETWEEN 1 AND 6

FIND_IN_SET() используется, когда список значений находится в строке через запятую, IN используется со списком букв в запросе.

Answer 2

SELECT qcat.name,
COUNT( CASE WHEN qas.state = "todo" THEN 1 END ) AS gtotal,
COUNT( CASE WHEN qas.state = "gradedright" THEN 1 END ) AS rightanswer, 
COUNT( CASE WHEN qas.state = "gradedwrong" THEN 1 END ) AS wronganswer, 
SUM(qas.fraction) AS grade,
quiza.id 
FROM mdl_quiz_attempts quiza
JOIN mdl_question_attempts qa ON qa.questionusageid = quiza.uniqueid 
JOIN mdl_question_attempt_steps qas ON qas.questionattemptid = qa.id 
JOIN mdl_question qstn ON ( qa.`questionid` = qstn.id ) 
JOIN mdl_question_categories qcat ON ( qstn.`category` = qcat.id ) 
WHERE quiza.id=1173 and FIND_IN_SET(qstn.id, "1,2,3,4,5,6") GROUP BY quiza.id,qcat.name