mysql - 如何对所有 count(case) 子列求和？

Question

我正在创建一个表格，该表格可以计算三列中的所有“异常”数据并将这些列相加作为总数。

SELECT

  COUNT(CASE WHEN p_eyes <> 'Normal' THEN 1 END) AS 'abnormalEyes',
  COUNT(CASE WHEN p_ears <> 'Normal' THEN 1 END) AS 'abnormalEars',
  COUNT(CASE WHEN p_nose <> 'Normal' THEN 1 END) AS 'abnormalNose'

FROM student_physical_record_exam_grade_eleven;

这将从这三列计算所有非“正常”。

有什么办法可以将这三列合计为“眼睛/耳朵/ Nose ”？

Answer 1

如果您只想对这些结果求和，可以将它们相加。最简单的方法是使用子查询:

SELECT *, abnormalEyes + abnormalEars + abnormalNose AS totalAbnormal
FROM   (SELECT COUNT(CASE WHEN p_eyes <> 'Normal' THEN 1 END) AS abnormalEyes,
               COUNT(CASE WHEN p_ears <> 'Normal' THEN 1 END) AS abnormalEars,
               COUNT(CASE WHEN p_nose <> 'Normal' THEN 1 END) AS abnormalNose
FROM   student_physical_record_exam_grade_eleven) t