Question

我在mysql中创建了这个函数，但该函数无效。动机是从包含每个科目，课堂，学期和学校课程中的学生分数的视图中获得最高分。 subjectid，termid，sessionid和class将从php传递给该函数。我的目标是获得最高分。

CREATE FUNCTION highestscore (class CHAR(20),subjectid INT, termid AS INT,sessionid INT) 
      RETURNS INT 
   BEGIN
      SELECT Max(total) AS hscore 
      FROM reportsheetsubjectsview 
      WHERE class=class AND subjectid=subjectid 
      AND termid=termid AND sessionid=sessionid
      RETURN hscore;
   END

已编辑的存储过程版本

CREATE DEFINER = root @ localhost PROCEDURE highestscore（IN subjectid INT，IN class VARCHAR（10），IN termid INT，IN sessionid INT，OUT highesttotalscore INT）确定性开始SELECT Max（总计）INTO highesttotalscore FROM scoreview WHERE class = class
AND subjectid = subjectid AND termid = termid AND sessionid = sessionid; 结束

Answer 1

在您的选择中添加GROUP BY子句。

SELECT Max(total) AS hscore 
      FROM reportsheetsubjectsview 
      WHERE class=class AND subjectid=subjectid 
      AND termid=termid AND sessionid=sessionid GROUP BY class, subjectid, termid, sessionid

将参数传递给Mysql函数

1 个答案: