如果为负，则仅显示SUM值-OnlyshowSUMvalueifitisnegative

0  

lets say you have a table name your_table which have two columns

假设你有一个表名为your_table,它有两列

name  balance
A      -1
B      10
A      -5

Now According to your description output will be

现在根据你的描述输出即可

 name balance
   A     -6

For this output query will be

对于此输出查询将是

select name,sum(balance)
  from your_table
  group by name
  having sum(balance)<0

0  

You could use a having condition:

你可以使用有条件:

SELECT   grouping_col, SUM(num_col)
FROM     mytable
GROUP BY grouping_col
HAVING   SUM(num_col) <0

0  

Try with case when

试试用的情况

SELECT column1,SUM(case when numcolumn<0 then numcolumn else 0 end) as sumval
FROM mytable
group by column1