Question

i have a table a_daily having
columns like

1.date
2.FromDate
3.Target
4.Cumulative_Target

I will be adding the rows daily
so every day with reference to fromdate and date the Cumulative_Target column will be updated as shown in the table

This is what i need to do:

    date                Fromdate      Target          Cumulative_Target
    2012-04-16    2012-04-16    500              500                  '(cycle1-started)
    2012-04-17    2012-04-16    500              1000    
    2012-04-18    2012-04-16    800              1800 
    '
    '
    '
    2012-05-15   2012-04-16     200             xxxxxx                 '(cycle1-completed)
    2012-05-16   2012-05-16     150             150                     '(cycle2-started)
    2012-05-17   2012-05-16     100             250
    2012-05-18   2012-05-16     700             950
    '
    '
    '
    '
    2012-06-15  2012-06-15      200             xxxxx                    '(Cycle2-completed)

so the fromdate in the table will be varying per cycle

The query i used for updation is :

UPDATE a_daily 
SET a_daily.Cumulative_Generation = sum(a_daily.Target) 
    between a_daily.Date and a_daily.From_Date

I dont know how to do makeup the computed column Please help me!!

Answer 1

Try this query –

SET @count = 0;
UPDATE a_daily
  SET Cumulative_Target = @count:= target + @count
ORDER BY date

…specify your order clause if needed