I have below data and I need to calculate LCM (Lowest calculate multiply) value based on group id using a T-SQL query. Your help would be appreciated.
Groupid GroupValue
------------------
1 2
1 4
1 6
2 5
2 5
2 10
3 3
3 12
3 6
3 9
Expected result is below.
Groupid GroupLCM
------------------
1 12
2 10
3 36
One possible way is to use tally tables like below
See working demo
; with detailedSet as
(
select
Groupid,
GroupValue=abs(GroupValue),
biggest=max(GroupValue) over (partition by Groupid),
totalNumbers= count(1) over (partition by Groupid)
from num
)
,
possibleLCMValues as
(
select Groupid, counter
from detailedSet b
cross apply
(
select counter= row_number() over ( order by (select null)) * biggest
from sys.objects o1 cross join sys.objects o2
)c
where c.counter%GroupValue =0
group by Groupid, counter
having count(1)=max(totalNumbers)
)
,
LCMValues as
(
select
Groupid,
LCM=min(counter)
from possibleLCMValues
group by Groupid
)
select * from LCMValues
I found the solution which I post on below stack flow question. In Final result table we just use max value again group id and we get LCM value.
Just note Like, I post this question for more optimize solution to remove for loop otherwise it working properly using for loop as well.
How to update the column without loop in SQL Server?
Related
(Select top 1 pvd.Code from PatientVisitDiags pvd
where pvd.PatientVisitId = pv.PatientVisitId
Order By pvd.Listorder) as "DX1",
(Select top 1 a.code from (Select top 2 pvd.Code,pvd.ListOrder from PatientVisitDiags pvd
where pvd.PatientVisitId = pv.PatientVisitId
Order By pvd.Listorder)a order by a.ListOrder DESC ) as "DX2",
(Select top 1 a.code from (Select top 3 pvd.Code,pvd.ListOrder from PatientVisitDiags pvd
where pvd.PatientVisitId = pv.PatientVisitId
Order By pvd.Listorder)a order by a.ListOrder DESC ) as "DX3",
(Select top 1 a.code from (Select top 4 pvd.Code,pvd.ListOrder from PatientVisitDiags pvd
where pvd.PatientVisitId = pv.PatientVisitId
Order By pvd.Listorder)a order by a.ListOrder DESC ) as "DX4",
(Select top 1 a.code from (Select top 5 pvd.Code,pvd.ListOrder from PatientVisitDiags pvd
where pvd.PatientVisitId = pv.PatientVisitId
Order By pvd.Listorder)a order by a.ListOrder DESC ) as "DX5"
The above code is what I am using currently (It is not optimal but is only being used once for a one time Data Export).
In the database that we are currently exporting from, there is a table PatientVisitDiags that has columns "ListOrder" and "Code". There can be between 1 and 5 codes. The ListOrder holds the number of that code. For example:
ListOrder|Code |
1 |M51.27 |
2 |M54.17 |
3 |G83.4 |
I am trying to export the Code to its corresponding Column in the new table(DX1,DX2..etc). If I sort by ListOrder I can get them in the order I need (Row 1 to DX1 | Row 2 to DX2 etc.) However when I run the above SQL code, If the source table only has 3 Codes DX4 and DX5 will repeat DX3. For Example:
DX1 |DX2 |DX3 |DX4 |DX5
M51.27 |M54.17 |G83.4 |G83.4 |G83.4
Is there a way to have TOP return NULL values if you Select TOP more than what is given? SQL Sever 2008 does not allow for OFFSET/FETCH, this is what I normally would have done given the option to select individual rows.
TL:DR
ID | Name
1 | Joe
2 | Eric
3 | Steve
4 | John
If I have a table like above and run
SELECT TOP 5 Name FROM Table
Is there anyway to return?
Joe
Eric
Steve
John
NULL
What you're really doing is pivoting. So pivot! Try this little query:
WITH Top5 AS (
SELECT TOP 5
Dx = 'DX' + Convert(varchar(11), Row_Number() OVER (ORDER BY pvd.Listorder)),
pvd.Code
FROM dbo.PatientVisitDiags pvd
WHERE pvd.PatientVisitId = #patientVisitId
)
SELECT *
FROM
Top5 t
PIVOT (Max(Code) FOR Dx IN (DX1, DX2, DX3, DX4, DX5)) p
;
To answer your second question about getting an unpivoted rowset, basically do the same thing but provide the 5 rows somehow and left join to the desired data.
WITH Data AS (
SELECT TOP 5
Seq = Row_Number() OVER(ORDER BY ID),
Name
FROM dbo.Table
ORDER BY ID
)
SELECT
n.Seq,
t.Name
FROM
(VALUES
(1), (2), (3), (4), (5) -- or a numbers-generating CTE perhaps
) n (Seq)
LEFT JOIN Top 5 t
ON n.Seq = t.Seq
;
Side note
The fact that you're doing this:
where pvd.PatientVisitId = pv.PatientVisitId
tells me you're not using ANSI joins. Stop. Don't do that any more. Put this join condition in the ON clause of a JOIN. It's the year 2016... why are you using join syntax from the last century?
Oh, and prefix the schema on the table names. Look it up--you'll find actual performance reasons why you should do that. It's not just about the time taken to find the correct schema, but also about the execution plan cache...
one at a time - answering the last question
create a table with a bunch of null
select top (5) col
from
(
select col from table1
union
select nulCol from nullTable
) tt
order by tt.col
I am a newbie poster but have spent a lot of time researching answers here. I can't quite figure out how to create a SQL result set using SQL Server 2008 R2 that should probably be using lead/lag from more modern versions. I am trying to aggregate data based on sequencing of one column, but there can be varying numbers of instances in each sequence. The only way I know a sequence has ended is when the next row has a lower sequence number. So it may go 1-2, 1-2-3-4, 1-2-3, and I have to figure out how to make 3 aggregates out of that.
Source data is joined tables that look like this (please help me format):
recordID instanceDate moduleID iResult interactionNum
1356 10/6/15 16:14 1 68 1
1357 10/7/15 16:22 1 100 2
1434 10/9/15 16:58 1 52 1
1435 10/11/15 17:00 1 60 2
1436 10/15/15 16:57 1 100 3
1437 10/15/15 16:59 1 100 4
I need to find a way to separate the first 2 rows from the last 4 rows in this example, based on values in the last column.
What I would love to ultimately get is a result set that looks like this, which averages the iResult column based on the grouping and takes the first instanceDate from the grouping:
instanceDate moduleID iResult
10/6/15 1 84
10/9/15 1 78
I can aggregate to get this result using MIN and AVG if I can just find a way to separate the groups. The data is ordered by instanceDate (please ignore the date formatting here) then interactionNum and the group separation should happen when the query finds a row where the interactionNum is <= than the previous row (will usually start over with '1' but not always, so prefer just to separate on a lower or equal integer value).
Here is the query I have so far (includes the joins that give the above data set):
SELECT
X.*
FROM
(SELECT TOP 100 PERCENT
instanceDate, b.ModuleID, iResult, b.interactionNum
FROM
(firstTable a
INNER JOIN
secondTable b ON b.someID = a.someID)
WHERE
a.someID = 2
AND b.otherID LIKE 'xyz'
AND a.ModuleID = 1
ORDER BY
instanceDate) AS X
OUTER APPLY
(SELECT TOP 1
*
FROM
(SELECT
instanceDate, d.ModuleID, iResult, d.interactionNum
FROM
(firstTable c
INNER JOIN
secondTable d ON d.someID = c.someID)
WHERE
c.someID = 2
AND d.otherID LIKE 'xyz'
AND c.ModuleID = 1
AND d.interactionNum = X.interactionNum
AND c.instanceDate < X.instanceDate) X2
ORDER BY
instanceDate DESC) Y
WHERE
NOT EXISTS (SELECT Y.interactionNum INTERSECT SELECT X.interactionNum)
But this is returning an interim result set like this:
instanceDate ModuleID iResult interactionNum
10/6/15 16:10 1 68 1
10/6/15 16:14 1 100 2
10/15/15 16:57 1 100 3
10/15/15 16:59 1 100 4
and the problem is that interactionNum 3, 4 do not belong in this result set. They would go in the next result set when I loop over this query. How do I keep them out of the result set in this iteration? I need the result set from this query to just include the first two rows, 'seeing' that row 3 of the source data has a lower value for interactionNum than row 2 has.
Not sure what ModuleID was supposed to be used, but I guess you're looking for something like this:
select min (instanceDate), [moduleID], avg([iResult])
from (
select *,row_number() over (partition by [moduleID] order by instanceDate) as RN
from Table1
) X
group by [moduleID], RN - [interactionNum]
The idea here is to create a running number with row_number for each moduleid, and then use the difference between that and InteractionNum as grouping criteria.
Example in SQL Fiddle
Here is my solution, although it should be said, I think #JamesZ answer is cleaner.
I created a new field called newinstance which is 1 wherever your instanceNumber is 1. I then created a rolling sum(newinstance) called rollinginstance to group on.
Change the last select to SELECT * FROM cte2 to show all the fields I added.
IF OBJECT_ID('tempdb..#tmpData') IS NOT NULL
DROP TABLE #tmpData
CREATE TABLE #tmpData (recordID INT, instanceDate DATETIME, moduleID INT, iResult INT, interactionNum INT)
INSERT INTO #tmpData
SELECT 1356,'10/6/15 16:14',1,68,1 UNION
SELECT 1357,'10/7/15 16:22',1,100,2 UNION
SELECT 1434,'10/9/15 16:58',1,52,1 UNION
SELECT 1435,'10/11/15 17:00',1,60,2 UNION
SELECT 1436,'10/15/15 16:57',1,100,3 UNION
SELECT 1437,'10/15/15 16:59',1,100,4
;WITH cte1 AS
(
SELECT *,
CASE WHEN interactionNum=1 THEN 1 ELSE 0 END AS newinstance,
ROW_NUMBER() OVER(ORDER BY recordID) as rowid
FROM #tmpData
), cte2 AS
(
SELECT *,
(select SUM(newinstance) from cte1 b where b.rowid<=a.rowid) as rollinginstance
FROM cte1 a
)
SELECT MIN(instanceDate) AS instanceDate, moduleID, AVG(iResult) AS iResult
FROM cte2
GROUP BY moduleID, rollinginstance
I am trying to get the simple SQL Server 2008 Recursive Query to work.
Following these examples:
http://msdn.microsoft.com/en-us/library/ms186243.aspx
and
SQL Server recursive query
I have a table, with id and parentID:
ID fParent fName
2 NULL root
3 2 Drug_Error
4 2 Incident
5 4 2007
6 4 2009
7 5 2007-1
8 7 2008-2
with the following query
with recury as (
Select
fs1.ID ,fs1.FParent,fs1.FName
from FoldersStructure as fs1
where fs1.FParent =null
union all
select fs2.id,fs2.FParent,fs2.FName
from FoldersStructure as fs2
inner join recury as r on fs2.FParent= r.ID
)
select ID,FParent,FName
from recury
where ID=8
I was hoping to get:
2 null root
4 2 incident
5 4 2007
7 5 2007-1
8 7 2007-2
But I only get the last one.
thanks in advance.
with recury as (
Select
fs1.ID ,fs1.FParent,fs1.FName
from FoldersStructure as fs1
where fs1.ID=8
union all
select fs2.id,fs2.FParent,fs2.FName
from FoldersStructure as fs2
inner join recury as r on fs2.ID= r.FParent
)
select ID,FParent,FName
from recury
order by ID
SQL-Fiddle
Remove the WHERE clause from the statement because it is limiting the resultset to rows where Id = 8. Based on the first comment below, I now understand your requirement! To use 8 as your starting point and to retrieve all parent rows:
WITH recury (Id, ParentId, Name, Level) AS
(
SELECT fs1.Id ,fs1.ParentId,fs1.Name, CONVERT(int, 0)
FROM FoldersStructure AS fs1
WHERE fs1.Id = 8
UNION ALL
SELECT fs2.Id,fs2.ParentId,fs2.Name, Level - 1
FROM FoldersStructure AS fs2
JOIN recury AS r ON fs2.Id = r.ParentId
)
SELECT Id, ParentId, Name, Level
FROM recury
ORDER BY Level;
This code will work if the Ids of the parent rows are not in numeric order. If your parent rows always guaranteed to be in numeric order, you can omit the Level column introduced in the CTE and sort on the Id column instead as per bummi's answer.
SQL fiddle example: http://sqlfiddle.com/#!3/2af0c/4
I made the following query for the SQL Server backend
SELECT TOP(1) (v.rownum + 99)
FROM
(
SELECT incrementNo-99 as id, ROW_NUMBER() OVER (ORDER BY incrementNo) as rownum
FROM proposals
WHERE [year] = '12'
) as v
WHERE v.rownum <> v.id
ORDER BY v.rownum
to find the first unused proposal number.
(It's not about the lastrecord +1)
But I realized ROW_NUMBER is not supported in access.
I looked and I can't find something similar.
Does anyone know how to get the same result as a ROW_NUMBER in access?
Maybe there's a better way of doing this.
Actually people insert their proposal No (incrementID) with no constraint. This number looks like this 13-152. xx- is for the current year and the -xxx is the proposal number. The last 3 digits are supposed to be incremental but in some case maybe 10 times a year they have to skip some numbers. That's why I can't have the auto increment.
So I do this query so when they open the form, the default number is the first unused.
How it works:
Because the number starts at 100, I do -99 so it starts at 1.
Then I compare the row number with the id so it looks like this
ROW NUMBER | ID
1 1 (100)
2 2 (101)
3 3 (102)
4 5 (104)<--------- WRONG
5 6 (105)
So now I know that we skip 4. So I return (4 - 99) = 103
If there's a better way, I don't mind changing but I really like this query.
If there's really no other way and I can't simulate a row number in access, i will use the pass through query.
Thank you
From your question it appears that you are looking for a gap in a sequence of numbers, so:
SELECT b.akey, (
SELECT Top 1 akey
FROM table1 a
WHERE a.akey > b.akey) AS [next]
FROM table1 AS b
WHERE (
SELECT Top 1 akey
FROM table1 a
WHERE a.akey > b.akey) <> [b].[akey]+1
ORDER BY b.akey
Where table1 is the table and akey is the sequenced number.
SELECT T.Value, T.next -1 FROM (
SELECT b.Value , (
SELECT Top 1 Value
FROM tblSequence a
WHERE a.Value > b.Value) AS [next]
FROM tblSequence b
) T WHERE T.next <> T.Value +1
I am trying to have a running average column in the SELECT statement based on a column from the n previous rows in the same SELECT statement. The average I need is based on the n previous rows in the resultset.
Let me explain
Id Number Average
1 1 NULL
2 3 NULL
3 2 NULL
4 4 2 <----- Average of (1, 3, 2),Numbers from previous 3 rows
5 6 3 <----- Average of (3, 2, 4),Numbers from previous 3 rows
. . .
. . .
The first 3 rows of the Average column are null because there are no previous rows. The row 4 in the Average column shows the average of the Number column from the previous 3 rows.
I need some help trying to construct a SQL Select statement that will do this.
This should do it:
--Test Data
CREATE TABLE RowsToAverage
(
ID int NOT NULL,
Number int NOT NULL
)
INSERT RowsToAverage(ID, Number)
SELECT 1, 1
UNION ALL
SELECT 2, 3
UNION ALL
SELECT 3, 2
UNION ALL
SELECT 4, 4
UNION ALL
SELECT 5, 6
UNION ALL
SELECT 6, 8
UNION ALL
SELECT 7, 10
--The query
;WITH NumberedRows
AS
(
SELECT rta.*, row_number() OVER (ORDER BY rta.ID ASC) AS RowNumber
FROM RowsToAverage rta
)
SELECT nr.ID, nr.Number,
CASE
WHEN nr.RowNumber <=3 THEN NULL
ELSE ( SELECT avg(Number)
FROM NumberedRows
WHERE RowNumber < nr.RowNumber
AND RowNumber >= nr.RowNumber - 3
)
END AS MovingAverage
FROM NumberedRows nr
Assuming that the Id column is sequential, here's a simplified query for a table named "MyTable":
SELECT
b.Id,
b.Number,
(
SELECT
AVG(a.Number)
FROM
MyTable a
WHERE
a.id >= (b.Id - 3)
AND a.id < b.Id
AND b.Id > 3
) as Average
FROM
MyTable b;
Edit: I missed the point that it should average the three previous records...
For a general running average, I think something like this would work:
SELECT
id, number,
SUM(number) OVER (ORDER BY ID) /
ROW_NUMBER() OVER (ORDER BY ID) AS [RunningAverage]
FROM myTable
ORDER BY ID
A simple self join would seem to perform much better than a row referencing subquery
Generate 10k rows of test data:
drop table test10k
create table test10k (Id int, Number int, constraint test10k_cpk primary key clustered (id))
;WITH digits AS (
SELECT 0 as Number
UNION SELECT 1
UNION SELECT 2
UNION SELECT 3
UNION SELECT 4
UNION SELECT 5
UNION SELECT 6
UNION SELECT 7
UNION SELECT 8
UNION SELECT 9
)
,numbers as (
SELECT
(thousands.Number * 1000)
+ (hundreds.Number * 100)
+ (tens.Number * 10)
+ ones.Number AS Number
FROM digits AS ones
CROSS JOIN digits AS tens
CROSS JOIN digits AS hundreds
CROSS JOIN digits AS thousands
)
insert test10k (Id, Number)
select Number, Number
from numbers
I would pull the special case of the first 3 rows out of the main query, you can UNION ALL those back in if you really want it in the row set. Self join query:
;WITH NumberedRows
AS
(
SELECT rta.*, row_number() OVER (ORDER BY rta.ID ASC) AS RowNumber
FROM test10k rta
)
SELECT nr.ID, nr.Number,
avg(trailing.Number) as MovingAverage
FROM NumberedRows nr
join NumberedRows as trailing on trailing.RowNumber between nr.RowNumber-3 and nr.RowNumber-1
where nr.Number > 3
group by nr.id, nr.Number
On my machine this takes about 10 seconds, the subquery approach that Aaron Alton demonstrated takes about 45 seconds (after I changed it to reflect my test source table) :
;WITH NumberedRows
AS
(
SELECT rta.*, row_number() OVER (ORDER BY rta.ID ASC) AS RowNumber
FROM test10k rta
)
SELECT nr.ID, nr.Number,
CASE
WHEN nr.RowNumber <=3 THEN NULL
ELSE ( SELECT avg(Number)
FROM NumberedRows
WHERE RowNumber < nr.RowNumber
AND RowNumber >= nr.RowNumber - 3
)
END AS MovingAverage
FROM NumberedRows nr
If you do a SET STATISTICS PROFILE ON, you can see the self join has 10k executes on the table spool. The subquery has 10k executes on the filter, aggregate, and other steps.
Want to improve this post? Provide detailed answers to this question, including citations and an explanation of why your answer is correct. Answers without enough detail may be edited or deleted.
Check out some solutions here. I'm sure that you could adapt one of them easily enough.
If you want this to be truly performant, and arn't afraid to dig into a seldom-used area of SQL Server, you should look into writing a custom aggregate function. SQL Server 2005 and 2008 brought CLR integration to the table, including the ability to write user aggregate functions. A custom running total aggregate would be the most efficient way to calculate a running average like this, by far.
Alternatively you can denormalize and store precalculated running values. Described here:
http://sqlblog.com/blogs/alexander_kuznetsov/archive/2009/01/23/denormalizing-to-enforce-business-rules-running-totals.aspx
Performance of selects is as fast as it goes. Of course, modifications are slower.