sql-在统一表上有4个查询,更好的要领？

今朝,我正在执行一个查询,个中包括3个子查询,
全部查询都在统一张表上,
全部查询都有差异的where子句

我曾思量过要举办小组相助,但这会粉碎SUM()

这是查询

SELECT SUM(club) AS club,(SELECT COUNT(id) FROM action_6_members WHERE SUBSTR(CODE,1,1) = '9') AS 5pts,1) = 'A') AS 10pts,1) NOT IN('9','A')) AS General
FROM action_6_members;

这是表明

id  select_type  table             type  rows  Extra        
1   PRIMARY      action_6_members  ALL   1471               
4   SUBQUERY     action_6_members  ALL   1471  Using where  
3   SUBQUERY     action_6_members  ALL   1471  Using where  
2   SUBQUERY     action_6_members  ALL   1471  Using where  

SELECT SUM(club) AS club,SUM(CASE WHEN SUBSTR(CODE,1) = '9' THEN 1 ELSE 0 END) AS 5pts,1) = 'A' THEN 1 ELSE 0 END) AS 10pts,'A') THEN 1 ELSE 0 END) AS General
  FROM action_6_members;

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