创建2张表 一张t_shuiguo 水果表 一张t_supermarket 超市表
 
现在我要查一个超市的各区水果价格的汇总
 
如下: 表A
 

那么首先水果表 是可以动态添加的 所有A表中的列 是动态的 先不考虑
 
先看下静态的 如果就是这么4个水果
 
那么SQL可以这么写 (参考了网上一些列子)
 
-- 静态sql
 
01
select ifnull(groups,'total') as groups,
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sum(if(name='苹果',prices,0)) as '苹果',
04  www.2cto.com  
 
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    sum(if(name='梨',prices,0)) as '梨',
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sum(if(name='橘子',prices,0)) as '橘子',
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sum(if(name='樱桃',prices,0)) as '樱桃',
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sum(if(name='total',prices,0)) as 'totals'
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from
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(select A.groups as groups,IFNULL(A.name,'total') as name ,sum(A.price) as prices
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from
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(select
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m.groups as groups ,s.name as name,m.price as price
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from t_supermarket  m
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inner join t_shuiguo s
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on m.shuiguo = s.id
28  www.2cto.com  
 
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) A
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group by groups, name
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with rollup
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having groups is not null
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) B
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 group by groups
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 with rollup
 

 
然后比较费劲的就是动态的 需要用到存储过程
 
如下：
 
001
-- 定义存储过程结束符
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delimiter $$
004
 
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-- 有先删除 再创建过程
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drop procedure if exists  searchShuiguo $$
008
 
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create procedure searchShuiguo()
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begin
012
 
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-- 定义sql前端
014
 
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declare v_1 varchar(1000) default ' SELECTIFNULL(groups,\'total\') as groups ';
016
 
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-- 定义sql 后端
018
 
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declare v_2 varchar(1000) default ' from (select groups,IFNULL(code,\'total\') as code ,sum(A.price) as prices  www.2cto.com  
020
 
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from (
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selectm.groups as groups ,s.code as code,m.price as price
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from t_supermarket  m inner join t_shuiguo s on m.shuiguo = s.id
026
 
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) A
028
 
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group by groups,
030
 
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code with rollup having groups is not null
032
 
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) B
034
 
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group by groups
036
 
037
with rollup';
038
 
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-- 定义临时参数 
040
 
041
declare v_temp varchar(2000);
042
 
043
-- 定义要遍历的变量
044  www.2cto.com  
 
045
declare v_shuiguo varchar(100) ;
046
 
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-- 定义结束变量
048
 
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declare stop int default 0;
050
 
051
-- 定义游标 去查水果列表
052
 
053
declare cur cursor for select code from t_shuiguo ;
054
 
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-- 一个没找到的回调设置
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declare continue handler for not found set stop = 1; 
058
 
059
-- 游标 遍历 拼接sql字符串
060
 
061
OPEN cur;
062
 
063
 FETCH cur INTO v_shuiguo;
064  www.2cto.com  
 
065
 WHILE stop = 0 
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DO
068
 
069
   if v_temp = '' then
070
 
071
set v_temp = CONCAT(v_1,'sum(if(code =\'',v_shuiguo,'\'');
072
 
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set v_1 = CONCAT(v_temp,',prices,0)) as ',v_shuiguo);
074
 
075
else
076
 
077
   set v_temp  = '';
078
 
079
set v_temp = CONCAT(v_1,',','sum(if(code =\'',v_shuiguo,'\'','');
080
 
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set v_1 = CONCAT(v_temp,',prices,0)) as ',v_shuiguo);
082  www.2cto.com  
 
083
end if;
084
 
085
FETCH cur INTO v_shuiguo;
086
 
087
 END WHILE;
088
 
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CLOSE cur; 
090
 
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set @v_result = CONCAT(v_1,', sum(if(code=\'total\',prices,0)) as \'total\'');
092
 
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set @v_result = CONCAT(@v_result,v_2);
094
 
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-- 执行sql
096
 
097
prepare stmt from @v_result;
098
 
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EXECUTE stmt ;
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   www.2cto.com  
101
deallocate prepare stmt;
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end $$
哦了
 
call searchShuiguo  () 就可以了