select
pow(sns_examdetail.SCORE-avg(sns_examdetail.SCORE),2) as score_pow ,
sum(pow(sns_examdetail.SCORE-avg(sns_examdetail.SCORE),2)) as sum_pow
from
sns_examdetail,sns_exam,ctb_papers,ctb_subject
where
sns_examdetail.EXAM_ID = sns_exam.EXAM_ID
and
sns_exam.PAPER_ID = ctb_papers.PAPER_ID
and
sns_examdetail.SUBJECT_ID = ctb_subject.SUBJECT_ID
and
ctb_subject.SUBJECT_ID = ctb_papers.SUBJECT_ID
and
sns_examdetail.PROBLEM_ID is null
and
sns_examdetail.STATUS <> 0
and
sns_exam.EXAM_NAME = 'XXXXXXXXX'
and
sns_exam.AREA_ID = '50'
group by subject_name
为什么select中的前半句话可以取得结果,而后半句话就说Invalid use of group function?郁闷的要死
pow(sns_examdetail.SCORE-avg(sns_examdetail.SCORE),2) as score_pow ,
sum(pow(sns_examdetail.SCORE-avg(sns_examdetail.SCORE),2)) as sum_pow
from
sns_examdetail,sns_exam,ctb_papers,ctb_subject
where
sns_examdetail.EXAM_ID = sns_exam.EXAM_ID
and
sns_exam.PAPER_ID = ctb_papers.PAPER_ID
and
sns_examdetail.SUBJECT_ID = ctb_subject.SUBJECT_ID
and
ctb_subject.SUBJECT_ID = ctb_papers.SUBJECT_ID
and
sns_examdetail.PROBLEM_ID is null
and
sns_examdetail.STATUS <> 0
and
sns_exam.EXAM_NAME = 'XXXXXXXXX'
and
sns_exam.AREA_ID = '50'
group by subject_name
为什么select中的前半句话可以取得结果,而后半句话就说Invalid use of group function?郁闷的要死
max(pow(sns_examdetail.SCORE-avg(sns_examdetail.SCORE),2)) as score_pow
max(pow(sns_examdetail.SCORE-avg(sns_examdetail.SCORE),2)) as score_pow
这句语法不对,对已经AVG了,怎么再对它进行SUM?同样去MAX也是错误的。