Question

I have a table called temp_reading. It has the following columns (consumption is an index key):

id consumption total
1  100
1  200
1  300
1  400
2  50
2  100
3  200
4  250

Now I want to display total as

id   consumption  total
1    100          100
1    200          300
1    300          600
1    300          900
2    50           50
2    100          150
3    200          200
4    250          250

Is it possible to display like the above?

I tried the following query:

SELECT id,consumption,sum(consumption) as total 
FROM temp_reading 
GROUP BY consumption;

Please help me solve this.

Answer 1

Try this:

SELECT id, consumption, IF(@s=@s:=id, @s2:=@s2+consumption, @s2:=consumption) AS total
FROM temp_reading, (SELECT @s:=0, @s2:=0);