Php 找到一个您熟悉的格式/缩进方案，并始终如一地应用它；你会很高兴你这么做的。尽管如此，出色的工作；我会投票赞成：）谢谢你宝贵的时间，我现在已经格式化了查询，谢谢Ed Gibbs的努力。你们真了不起。很好的工作。我爱你。@EdGibbs-为新用户解释聚合函数很

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找到一个您熟悉的格式/缩进方案，并始终如一地应用它；你会很高兴你这么做的。尽管如此，出色的工作；我会投票赞成：）谢谢你宝贵的时间，我现在已经格式化了查询，谢谢Ed Gibbs的努力。你们真了不起。很好的工作。我爱你。@EdGibbs-为新用户解释聚合函数很好！如果您能在我的查询中发现任何低效，我将不胜感激。我可以看到很多范围，但无法指出任何明显的低效。这种类型的东西在MySQL中很复杂，所以效率会受到影响。建议之一：更好地格式化查询。您有三个级别的子查询，没有缩进和分隔

SELECT

from

WHERE

from

groupby

。在我能理解它之前，我不得不复制和缩进。我建议您找到一个您熟悉的格式/缩进方案，并始终如一地应用它；你会很高兴你这么做的。尽管如此，出色的工作；我会投票赞成：）谢谢你宝贵的时间，我现在已经格式化了查询，谢谢Ed Gibbs的努力。你们真了不起。很好的工作。我爱你。@EdGibbs-为新用户解释聚合函数很好！

SELECT
  Name,
  SUM(C1Points) AS TotalC1,
  SUM(C2Points) AS TotalC2,
  SUM(C3Points) AS TotalC3,
  SUM(C1Points + C2Points + C3Points) AS TotalAll
FROM myTable
WHERE Section = 'Section1'
GROUP BY Name
ORDER BY TotalAll DESC
LIMIT 2

SELECT
  Name,
  Section,
  SUM(C1Points) AS TotalC1,
  SUM(C2Points) AS TotalC2,
  SUM(C3Points) AS TotalC3,
  SUM(C1Points + C2Points + C3Points) AS TotalAll
FROM myTable
GROUP BY Name, Section
ORDER BY Section, TotalAll DESC

Section 1 first place name and scores
Section 1 second place name and scores
Section 1 third place name and scores
. . .
Section 1 last place name and scores
Section 2 first place name and scores
Section 2 second place name and scores
and so on...

CREATE TABLE STUDENT (NAME VARCHAR(10), SECTION VARCHAR(20), 
                  C1 INTEGER, C2 INTEGER, C3 INTEGER);

INSERT INTO STUDENT VALUES ('S1','Section1',5,0,3),
                ('S2','Section2',0,0,5),
                ('S3','Section3',5,5,5),
                ('S4','Section3',3,3,0),
                ('S5','Section1',5,0,3),
                ('S6','Section2',0,1,0),
                ('S7','Section3',0,0,0),
                ('S8','Section3',5,0,5),
                ('S9','Section1',5,0,3),
                ('S10','Section2',0,3,0),
                ('S11','Section1',3,0,0),
                ('S12','Section3',5,5,5),
                ('S13','Section1',0,1,1),
                ('S14','Section2',3,5,0),
                ('S15','Section3',1,0,0);

ALTER TABLE STUDENT ADD COLUMN TOTAL INTEGER;

UPDATE STUDENT SET TOTAL = C1+C2+C3;

   SELECT SECTION,
       NAME,
       C1,
       C2,
       C3,
       TOTAL
FROM STUDENT
WHERE CONCAT(SECTION,TOTAL) IN
    (SELECT IDENTIFIER
     FROM
       (SELECT CONCAT(SECTION,MAX(TOTAL)) AS IDENTIFIER,
               SECTION,
               MAX(TOTAL) AS MARKS
        FROM STUDENT
        GROUP BY SECTION
        UNION SELECT CONCAT(SECTION,MAX(TOTAL)) AS IDENTIFIER,
                     SECTION,
                     MAX(TOTAL) AS MAKRS
        FROM STUDENT AS A
        WHERE TOTAL <
            (SELECT MAX(TOTAL)
             FROM STUDENT
             WHERE SECTION = A.SECTION)
        GROUP BY SECTION) AS RESULT)
ORDER BY SECTION,
         TOTAL DESC