Mysql 如果为空，则分组结果值

我无法执行此查询：

表:

------------
NOTES  | TOTAL
------------
NULL    |  23
NULL    |  12
pay1    | -13
pay2    | -23
-------------

结果:

------------
NOTES   | TOTAL
------------
SELL    |  35
pay1    | -13
pay2    | -23
-------------

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我需要对所有空字段和名称为“SELL”的组求和。

使用IF条件语句检查名称列作为空值，并替换为“SELL” 文本

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仅空值-S或您希望按

注释进行分组

？仅对空值进行分组和求和。贾罗德的答案是正确的。

select IF(name is  NULL, "SELL", name) as name, sum(total) as total from content group by name;

select IFNULL(NOTES,'SELL') n,SUM(TOTAL) FROM records GROUP BY n;

SELECT 
IFNULL(NOTES,'SELL')as NOTES,
SUM(TOTAL)  as TOTAL
FROM records 
GROUP BY notes
ORDER BY IFNULL(NOTES,'a')