Hello SQL gurus!
I am trying to write a query that will return a set of continguous rows
from a table, and limit the number of rows returned when a maximum
total has been reached by adding a value in one of the columns.
For example, the two columns below represent 2 columns in a table.
a 2
b 2
c 2
d 3
e 4
f 5
g 5
I want to start at, say "c", and return all the rows after it as long
as the sum of the numbers in column 2 (starting at "c") don't exceed
10. The result I'm after would be thus
c 2
d 3
e 4
....because 2 + 3 + 4 = 9 < 10
Any ideas? Many thanks. 4 10401
Try this
declare @t table(i char(10), id int)
insert into @t values('a',2)
insert into @t values('b',1)
insert into @t values('c',3)
insert into @t values('d',3)
insert into @t values('e',2)
insert into @t values('f',2)
insert into @t values('g',2)
insert into @t values('h',2)
select i, id from(
select i, id, (select sum(id) from @t where i<=T.i and i>='c') as 'Sum'
from @t T) M
where sum<=10
Madhivanan
Madihivanan, many thanks for this. It works perfectly! You've made
me think more about nested sets and expanded my SQL knowledge.
Please post DDL, so that people do not have to guess what the keys,
constraints, Declarative Referential Integrity, datatypes, etc. in your
schema are. Sample data is also a good idea, along with clear
specifications.
CREATE TABLE Foobar
(sort_order CHAR(1) NOT NULL PRIMARY KEY,
val INTEGER NOT NULL); I want to start at, say "c", and return all the rows after it as
long as the sum of the numbers in column 2 (starting at "c") don't
exceed 10. <<
SELECT @my_starter AS start, MAX(F1.sort_ord er) AS finish
FROM Foobar AS F1
WHERE @my_starter <= F1.sort_order
AND 10 <= (SELECT SUM(F2.val)
FROM Foobar AS F2
WHERE F2.sort_order
BETWEEN @my_starter AND F1.sort_order)
Thanks Joe, however this SQL doesn't produce the result I'm after. The
SQL by Madhivanan above was spot on. Thanks anyway. This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics |
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