Re: [SQL] summing tables

[Dani Oderbolz]

Erik Thiele wrote:

hi,

i have a table consisting of 4 integers.

seq is for making the table ordered. (ORDER BY SEQ ASC)
a,b,c maybe null
seq | a  | b  | c 
-----+----+----+---
  0 |  1 |  2 | 3
  1 |  1 |  2 |  
  2 |  5 |  7 |  
  3 | -2 | -4 |  

i am needing a sql statement to do

c=a+b+"the c of the row with seq one less than myself"

this statement has to run over the whole table, in seq order.

how can this be acomplished???

cu&thanks
erik
 

Hi Erik,
this should do the trick:
(I have not yet considered the NULLS though...)
UPDATE table t set c = a + b + (Select c from table tt where tt.seq = 
t.seq -1)

Cheers, Dani



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