Table data look like this
id val
1 4
2 2
3 1
I want result of subtract valu of val field in one sql statement.
like it should be like 4-2-1 = 1 if order by id asc, 1-2-4 = -5 if order by id desc.
You can try this
DECLARE #Table TABLE(
ID INT,
Val INT
)
INSERT INTO #Table (ID,Val) SELECT 1, 4
INSERT INTO #Table (ID,Val) SELECT 2, 2
INSERT INTO #Table (ID,Val) SELECT 3, 1
SELECT SUM(Val * CASE WHEN RowID = 1 THEN 1 ELSE -1 END)
FROM (
SELECT *,
ROW_NUMBER() OVER (ORDER BY ID) RowID
FROM #Table
) sub
You can declare a variable and increment it in the select statement:
declare #sum float
select #sum = case when #sum is null then value else #sum - value end
from YourTable
order by id
select #sum
To reverse the subtraction order, change order by id to order by id desc.
if you want to use just the sql without temp tables or variables:
select fromid.val - sumid.val
from (
select val
from t
where id = (
select min(id)
from t
)
) fromid cross join (
select sum(val) as val
from t
where id > (
select min(id)
from t
)
) sumid
Related
Sample data:
create table #temp (id int, qty int, checkvalue int)
insert into #temp values (1,1,3)
insert into #temp values (2,2,3)
insert into #temp values (3,1,3)
insert into #temp values (4,1,3)
According to data above, I would like to show exact number of lines from top to bottom where sum(qty) = checkvalue. Note that checkvalue is same for all the records all the time. Regarding the sample data above, the desired output is:
Id Qty checkValue
1 1 3
2 2 3
Because 1+2=3 and no more data is needed to show. If checkvalue was 4, we would show the third record: Id:3 Qty:1 checkValue:4 as well.
This is the code I am handling this problem. The code is working very well.
declare #checkValue int = (select top 1 checkvalue from #temp);
declare #counter int = 0, #sumValue int = 0;
while #sumValue < #checkValue
begin
set #counter = #counter + 1;
set #sumValue = #sumValue + (
select t.qty from
(
SELECT * FROM (
SELECT
ROW_NUMBER() OVER (ORDER BY id ASC) AS rownumber,
id,qty,checkvalue
FROM #temp
) AS foo
WHERE rownumber = #counter
) t
)
end
declare #sql nvarchar(255) = 'select top '+cast(#counter as varchar(5))+' * from #temp'
EXECUTE sp_executesql #sql, N'#counter int', #counter = #counter;
However, I am not sure if this is the best way to deal with it and wonder if there is a better approach. There are many professionals here and I'd like to hear from them about what they think about my approach and how we can improve it. Any advice would be appreciated!
Try this:
select id, qty, checkvalue from (
select t1.*,
sum(t1.qty) over (partition by t2.id) [sum]
from #temp [t1] join #temp [t2] on t1.id <= t2.id
) a where checkvalue = [sum]
Smart self-join is all you need :)
For SQL Server 2012, and onwards, you can easily achieve this using ROWS BETWEEN in your OVER clause and the use of a CTE:
WITH Running AS(
SELECT *,
SUM(qty) OVER (ORDER BY id
ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) AS RunningQty
FROM #temp t)
SELECT id, qty, checkvalue
FROM Running
WHERE RunningQty <= checkvalue;
One basic improvement is to try & reduce the no. of iterations. You're incrementing by 1, but if you repurpose the logic behind binary searching, you'd get something close to this:
DECLARE #RoughAverage int = 1 -- Some arbitrary value. The closer it is to the real average, the faster things should be.
DECLARE #CheckValue int = (SELECT TOP 1 checkvalue FROM #temp)
DECLARE #Sum int = 0
WHILE 1 = 1 -- Refer to BREAK below.
BEGIN
SELECT TOP (#RoughAverage) #Sum = SUM(qty) OVER(ORDER BY id)
FROM #temp
ORDER BY id
IF #Sum = #CheckValue
BREAK -- Indicating you reached your objective.
ELSE
SET #RoughAverage = #CheckValue - #Sum -- Most likely incomplete like this.
END
For SQL 2008 you can use recursive cte. Top 1 with ties limits result with first combination. Remove it to see all combinations
with cte as (
select
*, rn = row_number() over (order by id)
from
#temp
)
, rcte as (
select
i = id, id, qty, sumV = qty, checkvalue, rn
from
cte
union all
select
a.id, b.id, b.qty, a.sumV + b.qty, a.checkvalue, b.rn
from
rcte a
join cte b on a.rn + 1 = b.rn
where
a.sumV < b.checkvalue
)
select
top 1 with ties id, qty, checkvalue
from (
select
*, needed = max(case when sumV = checkvalue then 1 else 0 end) over (partition by i)
from
rcte
) t
where
needed = 1
order by dense_rank() over (order by i)
I need to populate a new column in a table known as RowType, where if the ID column contains the same ID value as the one above RowType is populated with 'D', if the value is new then RowType is populate with 'H', how would the SQL code look to be able to do this?
I.e should look something like below:
RowType (to be populated), ID (already there)
H, 1
D, 1
D, 1
H, 2
D, 2
H, 3
D, 3
D, 3
Thanks
You can use Row_Number and case
select *, RowType = case when Row_Number() over (partition by id order by id) = 1 then 'H' else 'D' End from #yourid
Your input table:
create table #yourId (id int)
insert into #yourid (id) values
(1)
,(1)
,(1)
,(2)
,(2)
,(3)
,(3)
,(3)
Use ROW_NUMER concept :
CREATE TABLE #table(Id INT)
INSERT INTO #table(Id)
SELECT 1 UNION ALL
SELECT 1 UNION ALL
SELECT 1 UNION ALL
SELECT 2 UNION ALL
SELECT 2 UNION ALL
SELECT 3 UNION ALL
SELECT 3 UNION ALL
SELECT 3
SELECT CASE WHEN RowType = 1 THEN 'H' ELSE 'D' END RowType , Id
FROM
(
SELECT ROW_NUMBER() OVER (PARTITION BY Id ORDER BY id) RowType , Id
FROM #table
) A
Please try...
UPDATE tableName
SET RowType = CASE
WHEN ( ID = LAG( ID ) OVER ( ORDER BY ID ) ) THEN 'D'
ELSE 'H'
END
If you have any questions or comments, then please feel free to post a Comment accordingly.
Further Reading
https://learn.microsoft.com/en-us/sql/t-sql/functions/lag-transact-sql (for information on LAG()).
It may not be the best solution, however it can point you somewhere, and it works.
Go through the code carfuly and make sure you understand this.
create table yourTable (RowType char, id int)
insert into yourTable (RowType, id) values
('',1)
,('',1)
,('',1)
,('',2)
,('',2)
,('',3)
,('',3)
,('',3)
select
row_number() over (order by id) as rowNumber,
RowType,
id
into #tempTable
from yourTable
declare #maxRow int = (select max(rowNumber) from #tempTable)
declare #currentRow int = 1
while (#currentRow <= #maxRow)
begin
if (#currentRow = 1)
begin
update #tempTable
set RowType = 'H'
where rowNumber = #currentRow
end
else
begin
if (select id from #tempTable where rowNumber = #currentRow) = (select id from #tempTable where rowNumber = #currentRow - 1)
begin
update #tempTable
set RowType = 'D'
where rowNumber = #currentRow
end
else
begin
update #tempTable
set RowType = 'H'
where rowNumber = #currentRow
end
end
set #currentRow = #currentRow +1
end
-- update data in actual table, you can do below if only those two columns exist in table !!!
delete from yourTable
-- insert into table from updated temp table
insert into yourTable
select RowType, ID
from #tempTable
select * from yourTable
select * from #tempTable
-- drop temp table
drop table #tempTable
Let say I have a table:
ColumnA ColumnB
---------------------------------
1 10.75
4 1234.30
6 2000.99
How can I write a SELECT query that will result in the following:
ColumnA ColumnB
---------------------------------
1 10.75
2 0.00
3 0.00
4 1234.30
5 0.00
6 2000.99
You can use a CTE to create a list of numbers from 1 to the maximum value in your table:
; with numbers as
(
select max(ColumnA) as nr
from YourTable
union all
select nr - 1
from numbers
where nr > 1
)
select nr.nr as ColumnA
, yt.ColumnB
from numbers nr
left join
YourTable yt
on nr.nr = yt.ColumnA
order by
nr.nr
option (maxrecursion 0)
See it working at SQL Fiddle.
Please try:
declare #min int, #max int
select #min=MIN(ColumnA), #max=MAX(ColumnA) from tbl
select
distinct number ColumnA,
isnull(b.ColumnB, 0) ColumnB
from
master.dbo.spt_values a left join tbl b on a.number=b.ColumnA
where number between #min and #max
Create a TallyTable (or NumbersTable) - see this question: What is the best way to create and populate a numbers table?
With that table create an insert statement:
INSERT INTO YourTable (ColumnA, ColumnB)
SELECT Number FROM NumberTable
WHERE
NOT EXISTS (SELECT 1 FROM YourTable WHERE NumberTable.Number = YourTable.ColumnA)
-- Adjust this value or calculate it with a query to the maximum of the source table
AND NumberTable.Number < 230130
DECLARE #t TABLE (ID INT,Val DECIMAL(10,2))
INSERT INTO #t (ID,Val) VALUES (1,10.75)
INSERT INTO #t (ID,Val) VALUES (4,6.75)
INSERT INTO #t (ID,Val) VALUES (7,4.75)
declare #MinNo int
declare #MaxNo int
declare #IncrementStep int
set #MinNo = 1
set #MaxNo = 10
set #IncrementStep = 1
;with C as
(
select #MinNo as Num
union all
select Num + #IncrementStep
from C
where Num < #MaxNo
)
select Num,
CASE WHEN Val IS NOT NULL THEN Val ELSE 0.00 END AS NUMBER
from C
LEFT JOIN #t t
ON t.ID = c.Num
You could use a number-table or following trick to generate a sequence which you can LEFT OUTER JOIN with your table. I assume you want to determine the boundaries dynamically:
WITH Seq AS
(
SELECT TOP ((SELECT Max(ColumnA)FROM Table1) - (SELECT Min(ColumnA) FROM Table1) + 1)
Num = (SELECT Min(ColumnA) FROM Table1)+ Row_number() OVER (ORDER BY [object_id]) -1
FROM sys.all_objects)
SELECT ColumnA = Seq.Num,
ColumnB = COALESCE(t.ColumnB ,0.00)
FROM Seq
LEFT OUTER JOIN Table1 t
ON Seq.Num = t.ColumnA
Demo with your sample.
Worth reading: http://www.sqlperformance.com/2013/01/t-sql-queries/generate-a-set-1
I have my collect of table functions like these.
create function dbo.GetNumbers(#Start int, #End int)
returns #Items table
(
Item int
)
as
begin
while (#Start <= #End)
begin
insert into #Items
values (#Start)
set #Start = #Start + 1
end
return
end
Then I can use it to left join to my data table and every value will be there.
declare #min int, #max int
set #min = 10
set #max = 20
select gn.Item
from dbo.GetNumbers(#min, #max) gn
I have similar table functions for date ranges, times, timezones, etc.
I want to store the top 2 results in 2 variables.
create table t(id int);
insert into t (id) values (1),(2),(3),(4);
declare #id1 int
declare #id2 int
select top 2 #id1 = first id,
#id2 = next id
from t
SQLFiddle
Can I do it in one query without using a loop?
declare #id1 int,#id2 int
;with cte as (
select top (2) id
from t
order by id
)
select #id1 = min(id), #id2 = max(id)
from cte
select #id1,#id2
Fiddle demo
with cte as (
select top 2 id, row_number() over(order by id) as rn
from t
order by id
)
select
#id1 = (select id from cte where rn = 1),
#id2 = (select id from cte where rn = 2)
or
with cte as (
select top 2 id, row_number() over(order by id) as rn
from t
order by id
)
select
#id1 = max(case when rn = 1 then id end),
#id2 = max(case when rn = 2 then id end)
from cte
sql fiddle demo
You can use LEAD() for SQL Server 2012.
SELECT TOP 1 #id1 = ID, #id2 = LEAD(ID) OVER (ORDER BY ID) FROM t
SQLFiddle Demo
With two SELECT it's easy...
DECLARE #id1 INT
DECLARE #id2 INT
SELECT TOP 1 #id1 = x.id
FROM (SELECT *, ROW_NUMBER() OVER (ORDER BY id) RN FROM t) x
WHERE x.RN = 1
SELECT TOP 1 #id2 = x.id
FROM (SELECT *, ROW_NUMBER() OVER (ORDER BY id) RN FROM t) x
WHERE x.RN = 2
SELECT #id1, #id2
With SQL 2012 you clearly could
SELECT #id1 = id
FROM t ORDER BY id OFFSET 0 ROWS FETCH NEXT 1 ROWS ONLY
SELECT #id2 = id
FROM t ORDER BY id OFFSET 1 ROWS FETCH NEXT 1 ROWS ONLY
Or evein in 2008 you could
; WITH Base AS (
SELECT *, ROW_NUMBER() OVER (ORDER BY id) RN FROM t
)
SELECT #id1 = b1.id, #id2 = b2.id
FROM Base b1, Base b2
WHERE b1.RN = 1 AND B2.RN = 2
declare #id1 int
declare #id2 int
declare #table table(id int,rownum int)
insert into #table
select top 2 id,row_number() over( order by id) as rn from t
select #id1=case rownum when 1 then id else #id1 end,
#id2=case rownum when 2 then id end from #table
select #id1,#id2
SQL FIDDLE
More easy way with 2 selects:
declare #id1 int
declare #id2 int
select top 1 #id1 = id from t
select top 2 #id2 = id from t
select #id1, #id2
SQL Fiddle
I have some data like this:
row id
1 1
2 36
3 37
4 38
5 50
6 51
I would like to query it to look like this:
row id group
1 1 1
2 36 2
3 37 2
4 38 2
5 50 3
6 51 3
... so that I can GROUP BY where the numbers are consecutively sequential.
Also, looping/cursoring is out of the question since I'm working with a pretty large set of data, thanks.
;WITH firstrows AS
(
SELECT id, ROW_NUMBER() OVER (ORDER BY id) groupid
FROM Table1 a
WHERE id - 1 NOT IN (SELECT b.id FROM Table1 b)
)
SELECT id,
(
SELECT MAX(b.groupid)
FROM firstrows b
WHERE b.id <= a.id
) groupid
FROM Table1 a
with
data(row, id) as (
select *
from (
values
(1,1)
,(2,36)
,(3,37)
,(4,38)
,(5,50)
,(6,51)
) as foo(row, id)
),
anchor(row, id) as (
select row, id
from data d1
where not exists(select 0 from data d2 where d2.id = d1.id - 1)
)
select d1.*, dense_rank() over(order by foo.id) as thegroup
from
data d1
cross apply (select max(id) from anchor where anchor.id <= d1.id) as foo(id)
order by
d1.row
;
This solution does more work that is strictly necessary on the basis that there may be gaps in the sequence of row values, and on the assumption that those gaps should be ignored.
Set up test data:
DECLARE #table TABLE
(ROW INT,
id INT
)
INSERT #table
SELECT 1,1
UNION SELECT 2,36
UNION SELECT 3,37
UNION SELECT 4,38
UNION SELECT 5,50
UNION SELECT 6,51
Output query
;WITH grpCTE
AS
(
SELECT ROW, id,
ROW_NUMBER() OVER (ORDER BY ROW
) AS rn
FROM #table
)
,recCTE
AS
(
SELECT ROW, id, rn, 1 AS grp
FROM grpCTE
WHERE rn = 1
UNION ALL
SELECT g.row, g.id, g.rn, CASE WHEN g.id = r.id + 1 THEN r.grp ELSE r.grp + 1 END AS grp
FROM grpCTE AS g
JOIN recCTE AS r
ON g.rn = r.rn + 1
)
SELECT row, id, grp FROM recCTE
create table #temp
(
IDUnique int Identity(1,1),
ID int,
grp int
)
Insert into #temp(ID) Values(1)
Insert into #temp(ID) Values(36)
Insert into #temp(ID) Values(37)
Insert into #temp(ID) Values(38)
Insert into #temp(ID) Values(50)
Insert into #temp(ID) Values(51)
declare #IDUnique int
declare #PreviousUnique int
declare #ID int
declare #grp int
declare #Previous int
declare #Row int
DECLARE #getAccountID CURSOR SET #getAccountID = CURSOR FOR SELECT Row_Number() Over(Order by IDUnique) Row, IDUnique, ID From #temp
OPEN #getAccountID
FETCH NEXT FROM #getAccountID INTO #Row, #IDUnique, #ID
WHILE ##FETCH_STATUS = 0
BEGIN
IF(#Row = 1)
Begin
update #temp set grp = 1 Where IDUnique = #IDUnique
set #Previous = #ID
set #grp = 1
End
Else If (#Previous + 1 = #ID)
Begin
update #temp set grp = #grp Where IDUnique = #IDUnique
set #Previous = #ID
End
Else
Begin
set #Previous = #ID
set #grp = #grp + 1
update #temp set grp = #grp Where IDUnique = #IDUnique
End
FETCH NEXT FROM #getAccountID INTO #Row, #IDUnique, #ID
END
CLOSE #getAccountID
DEALLOCATE #getAccountID
Select * from #temp
Drop Table #temp
Select T.Id, T.Row, groupId as "Group", dr FROM tbrows T
Left Outer Join
(
Select min(id) as groupId,DENSE_RANK() over( order by min(id)) as dr, MIN(row-id) as d, Sum(1) as s FROM tbrows
Group BY (row-id)
) U
On (T.Id >= U.groupId) and (T.Id < U.groupId+U.s)
Order By T.Id