Subtract 2 Rows into Column multiple times and link back to header - sql-server

I have some terrible data that I need to turn into something that means something. I realise this isn't the best way to show I haven't used StackOverflow in ages and I am not sure on syntax.
I have tried to write some queries but really I am not sure where to start on this sort of query so any help would be much appreciated, Thanks.
I have a header table which links to a details table. In the details table I have 3 sets of 2 records where I want to get the difference between two columns.
Header Table
headerId
1
2
Detail Table
detailid|headerId|name|totalElapsedMs
1|1|Request1|100
2|1|Response1|1000
3|1|Request2|1100
4|1|Response2|1800
5|1|Request3|2000
6|1|Response3|2600
Results
I want to subtract the rows that match each other and then pivot them up to the header row as shown below.
headerId|Request1ElapsedMs|Request2ElapsedMs|Request3ElapsedMs
1|900|700|600

I think it's fairly straightforward to use the PIVOT operator on the Detail table to get the output you want. Assuming #Detail is your source table, something like:
SELECT
HeaderID
, COALESCE( [Response1], 0 ) - COALESCE( [Request1], 0 ) AS Request1ElapsedMs
, COALESCE( [Response2], 0 ) - COALESCE( [Request2], 0 ) AS Request2ElapsedMs
, COALESCE( [Response3], 0 ) - COALESCE( [Request3], 0 ) AS Request3ElapsedMs
FROM
(SELECT HeaderID, Name, TotalElapsedMs FROM #Detail) AS Detail
PIVOT (SUM( TotalElapsedMs ) FOR Name IN ( [Request1], [Response1], [Request2], [Response2], [Request3], [Response3] )) AS PivotedData

There are many examples of Pivot and/or Dynamic Pivot.
The only trick here is to flip the sign, and then aggregate
Example
Declare #YourTable Table ([detailid] int,[headerId] int,[name] varchar(50),[totalElapsedMs] int)
Insert Into #YourTable Values
(1,1,'Request1',100)
,(2,1,'Response1',1000)
,(3,1,'Request2',1100)
,(4,1,'Response2',1800)
,(5,1,'Request3',2000)
,(6,1,'Response3',2600)
Select *
From (
Select HeaderId
,Item = concat('Request',replace(replace(name,'Request',''),'Response',''),'ElapsedMs')
,Value = [totalElapsedMs]*IIF(left(name,3)='Res',1,-1)
From #YourTable
) src
Pivot (sum(Value) for Item in ([Request1ElapsedMs],[Request2ElapsedMs],[Request3ElapsedMs]) ) pvt
Returns
HeaderId Request1ElapsedMs Request2ElapsedMs Request3ElapsedMs
1 900 700 600
If it helps, the subquery "feeding" the pivot generates
HeaderId Item Value
1 Request1ElapsedMs -100
1 Request1ElapsedMs 1000
1 Request2ElapsedMs -1100
1 Request2ElapsedMs 1800
1 Request3ElapsedMs -2000
1 Request3ElapsedMs 2600

Related

How do I exclude rows when an incremental value starts over?

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

TSQL matching the first instances of multiple values in a resultset

Say I have part of a large query, as below, that returns a resultset with multiple rows of the same key information (PolNum) with different value information (PolPremium) in a random order.
Would it be possible to select the first matching PolNum fields and sum up the PolPremium. In this case I know that there are 2 PolNumber's used so given the screenshot of the resultset (yes I know it starts at 14 for illustration purposes) and return the first values and sum the result.
First match for PolNum 000035789547
(ROW 14) PolPremium - 32.00
First match for PolNum 000035789547
(ROW 16) PolPremium - 706043.00
Total summed should be 32.00 + 706043.00 = 706072.00
Query
OUTER APPLY
(
SELECT PolNum, PolPremium
FROM PN20
WHERE PolNum IN(SELECT PolNum FROM SvcPlanPolicyView
WHERE SvcPlanPolicyView.ControlNum IN (SELECT val AS ServedCoverages FROM ufn_SplitMax(
(SELECT TOP 1 ServicedCoverages FROM SV91 WHERE SV91.AccountKey = 3113413), ';')))
ORDER BY PN20.PolEffDate DESC
}
Resultset
Suppose that pic if the final result your query produces. Then you can do something like:
DECLARE #t TABLE
(
PolNum VARCHAR(20) ,
PolPremium MONEY
)
INSERT INTO #t
VALUES ( '000035789547', 32 ),
( '000035789547', 76 ),
( '000071709897', 706043.00 ),
( '000071709897', 1706043.00 )
SELECT t.PolNum ,
SUM(PolPremium) AS PolPremium
FROM ( SELECT * ,
ROW_NUMBER() OVER ( PARTITION BY PolNum ORDER BY PolPremium ) AS rn
FROM #t
) t
WHERE rn = 1
GROUP BY GROUPING SETS(t.PolNum, ( ))
Output:
PolNum PolPremium
000035789547 32.00
000071709897 706043.00
NULL 706075.00
Just replace #t with your query. Also I assume that row with minimum of premium is the first. You could probably do filtering top row in outer apply part but it really not clear for me what is going on there without some sample data.

Get the missing value in a sequence of numbers

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

How do I get the "Next available number" from an SQL Server? (Not an Identity column)

Technologies: SQL Server 2008
So I've tried a few options that I've found on SO, but nothing really provided me with a definitive answer.
I have a table with two columns, (Transaction ID, GroupID) where neither has unique values. For example:
TransID | GroupID
-----------------
23 | 4001
99 | 4001
63 | 4001
123 | 4001
77 | 2113
2645 | 2113
123 | 2113
99 | 2113
Originally, the groupID was just chosen at random by the user, but now we're automating it. Thing is, we're keeping the existing DB without any changes to the existing data(too much work, for too little gain)
Is there a way to query "GroupID" on table "GroupTransactions" for the next available value of GroupID > 2000?
I think from the question you're after the next available, although that may not be the same as max+1 right? - In that case:
Start with a list of integers, and look for those that aren't there in the groupid column, for example:
;WITH CTE_Numbers AS (
SELECT n = 2001
UNION ALL
SELECT n + 1 FROM CTE_Numbers WHERE n < 4000
)
SELECT top 1 n
FROM CTE_Numbers num
WHERE NOT EXISTS (SELECT 1 FROM MyTable tab WHERE num.n = tab.groupid)
ORDER BY n
Note: you need to tweak the 2001/4000 values int the CTE to allow for the range you want. I assumed the name of your table to by MyTable
select max(groupid) + 1 from GroupTransactions
The following will find the next gap above 2000:
SELECT MIN(t.GroupID)+1 AS NextID
FROM GroupTransactions t (updlock)
WHERE NOT EXISTS
(SELECT NULL FROM GroupTransactions n WHERE n.GroupID=t.GroupID+1 AND n.GroupID>2000)
AND t.GroupID>2000
There are always many ways to do everything. I resolved this problem by doing like this:
declare #i int = null
declare #t table (i int)
insert into #t values (1)
insert into #t values (2)
--insert into #t values (3)
--insert into #t values (4)
insert into #t values (5)
--insert into #t values (6)
--get the first missing number
select #i = min(RowNumber)
from (
select ROW_NUMBER() OVER(ORDER BY i) AS RowNumber, i
from (
--select distinct in case a number is in there multiple times
select distinct i
from #t
--start after 0 in case there are negative or 0 number
where i > 0
) as a
) as b
where RowNumber <> i
--if there are no missing numbers or no records, get the max record
if #i is null
begin
select #i = isnull(max(i),0) + 1 from #t
end
select #i
In my situation I have a system to generate message numbers or a file/case/reservation number sequentially from 1 every year. But in some situations a number does not get use (user was testing/practicing or whatever reason) and the number was deleted.
You can use a where clause to filter by year if all entries are in the same table, and make it dynamic (my example is hardcoded). if you archive your yearly data then not needed. The sub-query part for mID and mID2 must be identical.
The "union 0 as seq " for mID is there in case your table is empty; this is the base seed number. It can be anything ex: 3000000 or {prefix}0000. The field is an integer. If you omit " Union 0 as seq " it will not work on an empty table or when you have a table missing ID 1 it will given you the next ID ( if the first number is 4 the value returned will be 5).
This query is very quick - hint: the field must be indexed; it was tested on a table of 100,000+ rows. I found that using a domain aggregate get slower as the table increases in size.
If you remove the "top 1" you will get a list of 'next numbers' but not all the missing numbers in a sequence; ie if you have 1 2 4 7 the result will be 3 5 8.
set #newID = select top 1 mID.seq + 1 as seq from
(select a.[msg_number] as seq from [tblMSG] a --where a.[msg_date] between '2023-01-01' and '2023-12-31'
union select 0 as seq ) as mID
left outer join
(Select b.[msg_number] as seq from [tblMSG] b --where b.[msg_date] between '2023-01-01' and '2023-12-31'
) as mID2 on mID.seq + 1 = mID2.seq where mID2.seq is null order by mID.seq
-- Next: a statement to insert a row with #newID immediately in tblMSG (in a transaction block).
-- Then the row can be updated by your app.

SQL Select Statement For Calculating A Running Average Column

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.

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