I have a table like this one:
SELECT value FROM table;
value
1
3
13
1
5
I would like to add an accumulator column, so that I have this result:
value accumulated
1 1
3 4
13 17
1 18
5 23
How can I do this? What's the real name of what I want to do? Thanks
try this way:
select value,
(select sum(t2.value) from table t2 where t2.id <= t1.id ) as accumulated
from table t1
but if it will not work on your database, just add order by something
select value,
(select sum(t2.value) from table t2 where t2.id <= t1.id order by id ) as accumulated
from table t1
order by id
this works on an oracle ;) but it should on a sqlite too
Here's a method to create a running total without the inefficiency of summing all prior rows. (I know this question is 6 years old but it's one of the first google entries for sqlite running total.)
create table t1 (value integer, accumulated integer, id integer primary key);
insert into t1 (value) values (1);
insert into t1 (value) values (3);
insert into t1 (value) values (13);
insert into t1 (value) values (1);
insert into t1 (value) values (5);
UPDATE
t1
SET
accumulated = ifnull(
(
SELECT
ifnull(accumulated,0)
FROM
t1 ROWPRIOR
WHERE
ROWPRIOR.id = (t1.id -1 )),0) + value;
.headers on
select * from t1;
value|accumulated|id
1|1|1
3|4|2
13|17|3
1|18|4
5|23|5
This should only be run once after importing all the values. Or, set the accumulated column to all nulls before running again.
The operation is called a running sum. SQLite does not support it as is, but there are ways to make it work. One is just as Sebastian Brózda posted. Another I detailed here in another question.
