错误：``在包含外部引用的聚合表达式中指定了多个列。''

问题是您不能在聚合函数中组合外部和内部引用

(SELECt TOP 100 PERCENT SUM(CASE WHEN bands.StackPosition = b.StackPosition THEN 1 ELSE 0 END) * 100/ CASEWHEN COUNT(StudentScores_Subject.pkStudentScoreID) = 0 THEN 1ELSE COUNT(StudentScores_Subject.pkStudentScoreID) END   FROM PerformanceLevelReportBands b   WHERe b.fkPerformanceLevelReportID = @intPerfLevelReportId   ORDER BY SUM(CASE WHEN bands.StackPosition = b.StackPosition THEN 1 ELSE 0 END) * 100/ CASEWHEN COUNT(StudentScores_Subject.pkStudentScoreID) = 0 THEN 1ELSE COUNT(StudentScores_Subject.pkStudentScoreID)END) AS 'Percent'

因此将其更改为

(SELECt TOP 100 PERCENT SUM(CASE WHEN bb.StackPosition = b.StackPosition THEN 1 ELSE 0 END) * 100/ CASE  WHEN COUNT(StudentScores_Subject.pkStudentScoreID) = 0 THEN 1  ELSE COUNT(StudentScores_Subject.pkStudentScoreID) END   FROM PerformanceLevelReportBands b JOIN PerformanceLevelReportBands bb    ON bb.fkPerformanceLevelReportID =bands.fkPerformanceLevelReportID     AND b.fkPerformanceLevelReportID =bb.fkPerformanceLevelReportID   WHERe b.fkPerformanceLevelReportID = @intPerfLevelReportId   ORDER BY SUM(CASE WHEN bb.StackPosition = b.StackPosition THEN 1 ELSE 0 END) * 100/ CASE WHEN COUNT(StudentScores_Subject.pkStudentScoreID) = 0 THEN 1 ELSE COUNT(StudentScores_Subject.pkStudentScoreID) END) AS 'Percent'

这是更详尽的解释。