I want to find Missing Numbers in a table..Table Like this.
Sno Branch
1 ABC
2 ABC
3 ABC
5 ABC // 4th sno is missing
6 ABC
8 ABC // 7th sno is missing
10 ABC // 9th sno is missing
I found the missing SNo using this Query
ALTER proc [dbo].[K_RT_DCNoMissing]--1,50
as
begin
declare #id int
set #id = 0
declare #maxid int
--set #id = #fromvalue
select #maxid = (select count(*) dcno from K_RT_Dailyentryretail nolock)
create table #IDSeq
(
id int
)
while 0<#maxid--whatever you max is
begin
insert into #IDSeq values(#id)
set #id = #id + 1
set #maxid = #maxid - 1
-- print #maxid
end
select
s.id
from
#idseq s
left join K_RT_Dailyentryretail t on
s.id = t.dcno
where t.dcno is null order by s.id asc
drop table #IDSeq
end
I am getting out put like this..
MissingNo's
4
7
9
Now I want to Display Sno with Branch Name like.
MissingNo's Branch
4 ABC
7 ABC
9 ABC
How can i get the branch name...
Am getting output as
4 abc
4 cde
4 fgh
7 abc
7 cde
7 fgh
but what actually am expecting is
4 abc
7 cde
. ..
. ..
etc.
You can use a CTE to build a table of all the branches and the full range of numbers for each. Then left join that to the main table to find what is missing. This will allow you to get consecutive missing numbers, e.g. 3, 4 and 5 missing. You can adjust #minid and #maxid to whatever you want your range to be. If #maxid can be greater than 32767, then you will need to do something with batches of ranges.
declare #minid int, #maxid int
set #minid = 1
set #maxid = (select count(*) dcno from K_RT_Dailyentryretail with (nolock))
; with Branches as (
select distinct Branch from K_RT_Dailyentryretail
)
, CTE as
(
select #minid as Sno, Branch from Branches
union all
select Sno + 1, Branch from CTE where Sno < #maxid
)
select CTE.Sno, CTE.Branch from CTE
left outer join K_RT_Dailyentryretail k on k.Branch = CTE.Branch and CTE.Sno = k.Sno
where k.Sno is null
option (MAXRECURSION 32767);
SQLFiddle here: http://sqlfiddle.com/#!3/13653/13
I am considering that GAP between you number will be always of only 1 digit.
In this case following will work for you,
;With CTE as
(
select Sno,Branch,ROW_NUMBER() over (order by Sno) R
from C
)
select a.Sno+ 1,a.Branch from CTE as a
left join CTE as b on a.R + 1= b.R
where a.Sno + 1 <> b.Sno
One more thing is that, for missing row you want branch, I have thought that for missing row you want to have branch of previous row.
Assuming that each branch has it's own set of sno numbers, this works:
select sno-1 as sno, branch
from t1
where sno-1 NOT in (select sno from t1 as t2 where t1.branch = t2.branch)
and sno > 1
;
Which you can check here: http://sqlfiddle.com/#!3/daa81d/3
If sno is a unique key, let me know and I will revise the answer.
EDIT: Like AK47's answer, I'm assuming that the gap is only one row.
Related
I have a table with the following data:
Part Comp level item_nbr
-------------------------------
abc ab 1 1
null cd 2 2
null ef 3 3
cde gh 1 4
null ij 2 5
null kl 3 6
null mn 4 7
I would like to update the nulls to the value in each level 1, so every level that is >1 is updated with the level one value.
Part Comp level
---------------------
abc ab 1
abc cd 2
abc ef 3
cde gh 1
cde ij 2
cde kl 3
cde mn 4
I am at a loss as to how to achieve this on a very large dataset. Any help would be greatly appreciated!
To explain another way,
part level
abc 1
2
3
Then the next row is populated with another part
efg 1
2
2
etc.
Further clarification:
I need the string"abc" to be filled down with the string "abc" while the column fields below are null. The next row has a string of efg and the following column fields below are null, again, those fields should be filled down with the value "efg" and so on.
The level field = 1 will always have a part number, but all the other levels report up to the level 1 part, so should be populated identically. And repeat.
Hope this makes sense.
Use an updatable CTE with window functions:
with toupdate as (
select t.*,
max(part) over (partition by itm_nbr_not_null) as new_part
from (select t.*,
max(case when part is not null then item_nbr end) over (order by item_nbr) as itm_nbr_not_null
from t
) t
)
update toupdate
set part = new_part
where part is null;
You can run the CTE to see what is happening.
well, from your question what I understand is, you need to update the null column's value until you get a not null value. and you want to continue it up to the last row of the table.
for that scenario, I created a stored procedure, where I read the value of every n-th cell if it is null I changing it with the prev. cell's value, when the cell was not null.
Approach:
create a temporary table/ table variable.
add an extra column, which is basically identity, which will help to rank the column.
iterate a loop until the maximum row is reached.
in each iteration, read the cell value for the i-th row
4.1 if it is not null put it in a temporary variable.
4.2 else, replace/update the i-th cell's value with the temporary variable
continue it, until you reached up to the last row of the table/table variable.
look at my following snippets:
create proc DemoPost
as
begin
declare #table table(serial_no int identity(1,1), name varchar(30), text varchar(30), level int)
insert #table
select Name, Text, Level from Demo
declare #max as int = (select max(serial_no) from #table)
--select #max
declare #i as int =0
declare #temp as varchar(30)
declare #text as varchar(30)
while #i < #max
begin
set #i = #i +1
set #temp = (select name from #table where serial_no = #i)
-- if #temp is not null, fetch its value, otherwise, update/replace it with
-- previously gotten not-null cell's value.
if #temp is not null
begin
set #text = (select name from #table where serial_no = #i)
end
else
begin
update #table
set name = #text where serial_no = #i
end
end
select name, text, level from #table
end
You can update it using temporary table according to the given scenario i thought item_nbr is unique in row Hope this will help
SELECT *
INTO #TEMP
FROM URTablehere
DECLARE #PRev VARCHAR(MAX)
WHILE ( SELECT COUNT(*)
FROM URTablehere
) > 0
BEGIN
DECLARE #ID INT
DECLARE #Part VARCHAR(MAX)
DECLARE #Num INT
SELECT TOP ( 1 )
#ID = level ,
#Part = Part ,
#Num = item_nbr
FROM #TEMP
IF ( #ID = 1 )
BEGIN
SELECT #PRev = #Part
END
IF ( #ID > 1
AND #Part IS NULL
)
BEGIN
UPDATE URTablehere
SET Part = #PRev
WHERE item_nbr = #Num
END
DELETE
FROM #TEMP WHERE item_nbr=#Num
END
could someone please help? My starting table looks like this with 2 fields:
Name Counter
dave 2
Joe 3
I want my result to look like this:
Name Counter
dave 1
dave 2
joe 1
joe 2
joe 3
Essentially creating n number of records base on the counter and starts at 1. I tried to do a loop using counter as a variable, but the code just runs nonstop.. could someone help?
A procedural SQL Server solution:
declare #input table
(
name nvarchar(100)
,wantedrows int
,processed bit
,id uniqueidentifier
);
declare #output table
(
name nvarchar(100)
,rownum int
);
insert into #input
select 'Dave',3,0,newid()
union
select 'Joe',2,0,newid();
while exists(select * from #input where processed = 0)
begin
declare #currentid uniqueidentifier = (select top 1 id from #input where processed = 0);
declare #currentwantedrows int = (select wantedrows from #input where id = #currentid);
declare #i int = 0;
while #i < #currentwantedrows
begin
insert into #output
select name,#i+1
from #input
where id = #currentid;
set #i = #i + 1;
end;
update #input set processed = 1 where id = #currentid;
end
select name,wantedrows from #input;
select * from #output;
You can use a number-table or following trick using a system view to build a sequence:
WITH Nums AS
(
SELECT n = ROW_NUMBER() OVER (ORDER BY [object_id])
FROM sys.all_objects
)
SELECT Name, Counter = n
FROM Nums n CROSS JOIN Table1 t1
WHERE n BETWEEN 1 AND Counter
ORDER BY Name, Counter;
Demo
This view has only about 2000 rows, so if you need more you could use a number-table.
http://sqlperformance.com/2013/01/t-sql-queries/generate-a-set-1
( presuming SQL-Server )
Is a hundred copies enough?
create table #c (num)
insert into #c (num)
select 0 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
select T.Name, c1.num * 10 + c0.num + 1
from T, #c c1, #c c0
where c1.num * 10 + c0.num < T.Counter
drop table #c
You didn't say which version of Sybase. The old ones I've worked on didn't allow derived tables so I had to throw the values into a temp table. But you can see how to extend the idea. This may not be the best approach if this is something you need to do more than once though.
I have a report that needs the top 18 id codes for each case. Some cases only have all 18 rows and some only have a few. Here is an example of the output:
Case idcode value
2 3 122
2 6 52
2 15 121
3 1 111
3 3 555
3 6 322
What I need the output to have is 18 rows per record (idcodes 1-18) and to put "none" for the value if it is added. What is the best way to add in the missing rows if I do not know which ones are missing ahead of time?
Here is my query:
SELECT
rcl.CaseCaseId as Case, cce.StringValue as Value, cce.CorpIdCodeId as idcode
FROM
CaseIdCodeEntry AS cce
INNER JOIN
CorpIdCodes AS cid ON cce.CorpIdCodeId = cid.CorpIdCodeId
INNER JOIN
PhdRpt.ReportCaseList_542 AS rcl ON cce.CaseCaseId = rcl.CaseCaseId
WHERE
(cce.CorpIdCodeId < 19)
I would use a recursive CTE to auto-generate a numbered list of 1-18, and then LEFT JOIN off of that. Then use a CASE statement to adjust the Value field.
;WITH cte AS
( SELECT DISTINCT CaseCaseId AS CaseID, 1 AS idcode
FROM PhdRpt.ReportCaseList_542 UNION ALL
SELECT CaseID, idcode+1 FROM cte WHERE idcode < 18 )
SELECT cte.CaseID AS [Case],
CASE WHEN cce.CorpIdCodeId IS NULL THEN 'None' ELSE cce.StringValue END AS Value,
cte.idcode AS idcode
FROM cte
LEFT JOIN CaseIdCodeEntry cid ON cid.CorpCodeId = cte.idcode
LEFT JOIN CorpIdCodes cid ON cce.CorpIdCodeId = cid.CorpIdCodeId
LEFT JOIN PhdRpt.ReportCaseList_542 rcl ON cce.CaseCaseId = rcl.CaseCaseId
Try this seems works fine
create table #temp(iCase int, idcode int,value int)
Insert into #temp values(2,3,122)
Insert into #temp values(2,6,52)
Insert into #temp values(2,15,121)
Insert into #temp values(3,1,11)
Insert into #temp values(3,3,555)
Insert into #temp values(3,6,322)
create table #Val(Id int)
declare #count int =1
while (#count<=18)
begin
insert into #Val values(#count)
set #count=#count+1
end
DECLARE #CaseId INT
DECLARE #DataCursor CURSOR
SET #DataCursor = CURSOR FOR
SELECT distinct iCase
From #temp
OPEN #DataCursor
FETCH NEXT
FROM #DataCursor INTO #CaseId
WHILE ##FETCH_STATUS = 0
BEGIN
INSERT INTO #temp
SELECT #CaseId,Id,null
FROM #Val
WHERE Id NOT IN (
SELECT idcode
FROM #temp
WHERE iCase=#CaseId )
FETCH NEXT
FROM #DataCursor INTO #CaseId
END
CLOSE #DataCursor
DEALLOCATE #DataCursor
Select * from #temp
TL;DR SQL Fiddle
Like Jon of All Trades I also favour the use of a sequence (or number) table.
CREATE TABLE Seq ( seq_num int)
You can use this to populate the missing rows from your original data; assuming you have a table T holding your data
CREATE TABLE T ( case_num int
,code_id int
,value char(4))
You can use the following query to get your fully populated results
WITH All_Codes AS (
SELECT DISTINCT case_num, seq_num AS code_id
FROM T, Seq
)
SELECT All_Codes.case_num
,All_Codes.code_id
,CASE WHEN value IS NULL THEN 'none' ELSE value END AS value
FROM All_Codes LEFT JOIN T
ON All_Codes.case_num = T.case_num AND All_Codes.code_id = T.code_id
The result is
case_num code_id value
2 1 none
2 2 none
2 3 122
2 4 none
2 5 none
2 6 52
2 7 none
2 8 none
2 9 none
2 10 none
2 11 none
2 12 none
2 13 none
2 14 none
2 15 121
2 16 none
2 17 none
2 18 none
3 1 111
3 2 none
3 3 555
3 4 none
3 5 none
3 6 322
3 7 none
3 8 none
3 9 none
3 10 none
3 11 none
3 12 none
3 13 none
3 14 none
3 15 none
3 16 none
3 17 none
3 18 none
Humpty and Matt's solutions should work, but as a purist I'd recommend using a Numbers table rather than a cursor or CTE. It's simpler (IMHO) and for large quantities it should be significantly faster:
SELECT
X.CaseId, N.Number, X.Value
FROM
Numbers AS N
LEFT JOIN
(
SELECT
CICE.CaseCaseId AS CaseId, CICE.StringValue AS Value, CICE.CorpIdCodeId AS IdCode
FROM
CaseIdCodeEntry AS CICE
INNER JOIN CorpIdCodes AS CIC ON CICE.CorpIdCodeId = CIC.CorpIdCodeId
INNER JOIN PhdRpt.ReportCaseList_542 AS RCL ON CICE.CaseCaseId = RCL.CaseCaseId
) AS X ON N.Number = X.IdCode
WHERE
N.Number BETWEEN 1 AND 18
Incidentally, are you sure you need to join CaseIdCodeEntry to CorpIdCodes and ReportCaseList_542? If they're there to filter the data, that's fine, but as they're not contributing to the output I have to wonder.
This is the solution that I used. I used some of #Jon of All Trades and #huMpty duMpty code.
SELECT cice.CaseCaseId, cice.CorpIdCodeId, cice.DateValue, cice.DoubleValue, cice.StringValue, cic.Label
into #TT
FROM CaseIdCodeEntry AS cice INNER JOIN
CorpIdCodes AS cic ON cice.CorpIdCodeId = cic.CorpIdCodeId INNER JOIN
PhdRpt.ReportCaseList_542 AS rcl ON cice.CaseCaseId = rcl.CaseCaseId
WHERE (cice.CorpIdCodeId <= 18)
ORDER BY cice.CaseCaseId, cice.CorpIdCodeId
create table #Val(Id int)
declare #count int =1
while (#count<=18)
begin
insert into #Val values(#count)
set #count=#count+1
end
DECLARE #CaseId INT
DECLARE #DataCursor CURSOR
SET #DataCursor = CURSOR FOR
SELECT distinct CaseCaseId
From #TT
OPEN #DataCursor
FETCH NEXT
FROM #DataCursor INTO #CaseId
WHILE ##FETCH_STATUS = 0
BEGIN
INSERT INTO #TT
SELECT #CaseId,Id,null, null, null, 'none'
FROM #Val
WHERE Id NOT IN (
SELECT CorpIdCodeId
FROM #TT
WHERE CaseCaseId=#CaseId )
FETCH NEXT
FROM #DataCursor INTO #CaseId
END
CLOSE #DataCursor
DEALLOCATE #DataCursor
Select * from #TT
order by CaseCaseId, CorpIdCodeId
drop table #TT, #Val
I have a data table as below
#data
---------------
Account AccountType
---------------
1 2
2 0
3 5
4 2
5 1
6 5
AccountType 2 is headers and 5 is totals. Meaning accounts of type 2 have to look after the next 1 or 0 to determin if its Dim value is 1 or 0. Totals of type 5 have to look up at nearest 1 or 0 to determin its Dim value. Accounts of type 1 or 0 have there type as Dim.
Accounts of type 2 appear as islands so its not enough to just check RowNumber + 1 and same goes for accounsts of type 5.
I have arrived at the following table using CTE's. But can't find a quick way to go from here to my final result of Account, AccountType, Dim for all accounts
T3
-------------------
StartRow EndRow AccountType Dim
-------------------
1 1 2 0
2 2 0 0
3 3 5 0
4 4 2 1
5 5 0 1
6 6 5 1
Below code is MS TSQL copy paste it all and see it run. The final join on the CTE select statement is extremly slow for even 500 rows it takes 30 sec. I have 100.000 rows i need to handle. I done a cursor based solution which do it in 10-20 sec thats workable and a fast recursive CTE solution that do it in 5 sec for 100.000 rows, but it dependent on the fragmentation of the #data table. I should add this is simplified the real problem have alot more dimension that need to be taking into account. But it will work the same for this simple problem.
Anyway is there a fast way to do this using joins or another set based solution.
SET NOCOUNT ON
IF OBJECT_ID('tempdb..#data') IS NOT NULL
DROP TABLE #data
CREATE TABLE #data
(
Account INTEGER IDENTITY(1,1),
AccountType INTEGER,
)
BEGIN -- TEST DATA
DECLARE #Counter INTEGER = 0
DECLARE #MaxDataRows INTEGER = 50 -- Change here to check performance
DECLARE #Type INTEGER
WHILE(#Counter < #MaxDataRows)
BEGIN
SET #Type = CASE
WHEN #Counter % 10 < 3 THEN 2
WHEN #Counter % 10 >= 8 THEN 5
WHEN #Counter % 10 >= 3 THEN (CASE WHEN #Counter < #MaxDataRows / 2.0 THEN 0 ELSE 1 END )
ELSE 0
END
INSERT INTO #data VALUES(#Type)
SET #Counter = #Counter + 1
END
END -- TEST DATA END
;WITH groupIds_cte AS
(
SELECT *,
ROW_NUMBER() OVER (PARTITION BY AccountType ORDER BY Account) - Account AS GroupId
FROM #data
),
islandRanges_cte AS
(
SELECT
MIN(Account) AS StartRow,
MAX(Account) AS EndRow,
AccountType
FROM groupIds_cte
GROUP BY GroupId,AccountType
),
T3 AS
(
SELECT I.*, J.AccountType AS Dim
FROM islandRanges_cte I
INNER JOIN islandRanges_cte J
ON (I.EndRow + 1 = J.StartRow AND I.AccountType = 2)
UNION ALL
SELECT I.*, J.AccountType AS Dim
FROM islandRanges_cte I
INNER JOIN islandRanges_cte J
ON (I.StartRow - 1 = J.EndRow AND I.AccountType = 5)
UNION ALL
SELECT *, AccountType AS Dim
FROM islandRanges_cte
WHERE AccountType = 0 OR AccountType = 1
),
T4 AS
(
SELECT Account, Dim
FROM (
SELECT FlattenRow AS Account, StartRow, EndRow, Dim
FROM T3 I
CROSS APPLY (VALUES(StartRow),(EndRow)) newValues (FlattenRow)
) T
)
--SELECT * FROM T3 ORDER BY StartRow
--SELECT * FROM T4 ORDER BY Account
-- Final correct result but very very slow
SELECT D.Account, D.AccountType, I.Dim FROM T3 I
INNER JOIN #data D
ON D.Account BETWEEN I.StartRow AND I.EndRow
ORDER BY Account
EDIT with some time testing
SET NOCOUNT ON
IF OBJECT_ID('tempdb..#data') IS NULL
CREATE TABLE #times
(
RecId INTEGER IDENTITY(1,1),
Batch INTEGER,
Method NVARCHAR(255),
MethodDescription NVARCHAR(255),
RunTime INTEGER
)
IF OBJECT_ID('tempdb..#batch') IS NULL
CREATE TABLE #batch
(
Batch INTEGER IDENTITY(1,1),
Bit BIT
)
INSERT INTO #batch VALUES(0)
IF OBJECT_ID('tempdb..#data') IS NOT NULL
DROP TABLE #data
CREATE TABLE #data
(
Account INTEGER
)
CREATE NONCLUSTERED INDEX data_account_index ON #data (Account)
IF OBJECT_ID('tempdb..#islands') IS NOT NULL
DROP TABLE #islands
CREATE TABLE #islands
(
AccountFrom INTEGER ,
AccountTo INTEGER,
Dim INTEGER,
)
CREATE NONCLUSTERED INDEX islands_from_index ON #islands (AccountFrom, AccountTo, Dim)
BEGIN -- TEST DATA
INSERT INTO #data
SELECT TOP 100000 ROW_NUMBER() OVER(ORDER BY t1.number) AS N
FROM master..spt_values t1
CROSS JOIN master..spt_values t2
INSERT INTO #islands
SELECT MIN(Account) AS Start, MAX(Account), Grp
FROM (SELECT *, NTILE(10) OVER (ORDER BY Account) AS Grp FROM #data) T
GROUP BY Grp ORDER BY Start
END -- TEST DATA END
--SELECT * FROM #data
--SELECT * FROM #islands
--PRINT CONVERT(varchar(20),DATEDIFF(MS,#RunDate,GETDATE()))+' ms Sub Query'
DECLARE #RunDate datetime
SET #RunDate=GETDATE()
SELECT Account, (SELECT Dim From #islands WHERE Account BETWEEN AccountFrom AND AccountTo) AS Dim
FROM #data
INSERT INTO #times VALUES ((SELECT MAX(Batch) FROM #batch) ,'subquery','',DATEDIFF(MS,#RunDate,GETDATE()))
SET #RunDate=GETDATE()
SELECT D.Account, V.Dim
FROM #data D
CROSS APPLY
(
SELECT Dim From #islands V
WHERE D.Account BETWEEN V.AccountFrom AND V.AccountTo
) V
INSERT INTO #times VALUES ((SELECT MAX(Batch) FROM #batch) ,'crossapply','',DATEDIFF(MS,#RunDate,GETDATE()))
SET #RunDate=GETDATE()
SELECT D.Account, I.Dim
FROM #data D
JOIN #islands I
ON D.Account BETWEEN I.AccountFrom AND I.AccountTo
INSERT INTO #times VALUES ((SELECT MAX(Batch) FROM #batch) ,'join','',DATEDIFF(MS,#RunDate,GETDATE()))
SET #RunDate=GETDATE()
;WITH cte AS
(
SELECT Account, AccountFrom, AccountTo, Dim, 1 AS Counting
FROM #islands
CROSS APPLY (VALUES(AccountFrom),(AccountTo)) V (Account)
UNION ALL
SELECT Account + 1 ,AccountFrom, AccountTo, Dim, Counting + 1
FROM cte
WHERE (Account + 1) > AccountFrom AND (Account + 1) < AccountTo
)
SELECT Account, Dim, Counting FROM cte OPTION(MAXRECURSION 32767)
INSERT INTO #times VALUES ((SELECT MAX(Batch) FROM #batch) ,'recursivecte','',DATEDIFF(MS,#RunDate,GETDATE()))
You can select from the #times table to see the run times :)
I think you want a join, but using an inequality rather than an equality:
select tt.id, tt.dim1, it.dim2
from TallyTable tt join
IslandsTable it
on tt.id between it."from" and it."to"
This works for the data that you provide in the question.
Here is another idea that might work. Here is the query:
select d.*,
(select top 1 AccountType from #data d2 where d2.Account > d.Account and d2.AccountType not in (2, 5)
) nextAccountType
from #data d
order by d.account;
I just ran this on 50,000 rows and this version took 17 seconds on my system. Changing the table to:
CREATE TABLE #data (
Account INTEGER IDENTITY(1,1) primary key,
AccountType INTEGER,
);
Has actually slowed it down to about 1:33 -- quite to my surprise. Perhaps one of these will help you.
The SO Question has lead me to the following question.
If a table has 16 rows I'd like to add a field to the table with the numbers 1,2,3,4,5,...,16 arranged randomly i.e in the 'RndVal' field for row 1 this could be 2, then for row 2 it could be 5 i.e each of the 16 integers needs to appear once without repetition.
Why doesn't the following work? Ideally I'd like to see this working then to see alternative solutions.
This creates the table ok:
IF OBJECT_ID('tempdb..#A') IS NOT NULL BEGIN DROP TABLE #A END
IF OBJECT_ID('tempdb..#B') IS NOT NULL BEGIN DROP TABLE #B END
IF OBJECT_ID('tempdb..#C') IS NOT NULL BEGIN DROP TABLE #C END
IF OBJECT_ID('tempdb..#myTable') IS NOT NULL BEGIN DROP TABLE #myTable END
CREATE TABLE #B (B_ID INT)
CREATE TABLE #C (C_ID INT)
INSERT INTO #B(B_ID) VALUES
(10),
(20),
(30),
(40)
INSERT INTO #C(C_ID)VALUES
(1),
(2),
(3),
(4)
CREATE TABLE #A
(
B_ID INT
, C_ID INT
, RndVal INT
)
INSERT INTO #A(B_ID, C_ID, RndVal)
SELECT
#B.B_ID
, #C.C_ID
, 0
FROM #B CROSS JOIN #C;
Then I'm attempting to add the random column using the following. The logic is to add random numbers between 1 and 16 > then to effectively overwrite any that are duplicated with other numbers > in a loop ...
SELECT
ROW_NUMBER() OVER(ORDER BY B_ID) AS Row
, B_ID
, C_ID
, RndVal
INTO #myTable
FROM #A
DECLARE #rowsRequired INT = (SELECT COUNT(*) CNT FROM #myTable)
DECLARE #i INT = (SELECT #rowsRequired - SUM(CASE WHEN RndVal > 0 THEN 1 ELSE 0 END) FROM #myTable)--0
DECLARE #end INT = 1
WHILE #end > 0
BEGIN
SELECT #i = #rowsRequired - SUM(CASE WHEN RndVal > 0 THEN 1 ELSE 0 END) FROM #myTable
WHILE #i>0
BEGIN
UPDATE x
SET x.RndVal = FLOOR(RAND()*#rowsRequired)
FROM #myTable x
WHERE x.RndVal = 0
SET #i = #i-1
END
--this is to remove possible duplicates
UPDATE c
SET c.RndVal = 0
FROM
#myTable c
INNER JOIN
(
SELECT RndVal
FROM #myTable
GROUP BY RndVal
HAVING COUNT(RndVal)>1
) t
ON
c.RndVal = t.RndVal
SET #end = ##ROWCOUNT
END
TRUNCATE TABLE #A
INSERT INTO #A
SELECT
B_ID
, C_ID
, RndVal
FROM #myTable
If the original table has 6 rows then the result should end up something like this
B_ID|C_ID|RndVal
----------------
| | 5
| | 4
| | 1
| | 6
| | 3
| | 2
I don't understand your code, frankly
This will update each row with a random number, non-repeated number between 1 and the number of rows in the table
UPDATE T
SET SomeCol = T2.X
FROM
MyTable T
JOIN
(
SELECT
KeyCol, ROW_NUMBER() OVER (ORDER BY NEWID()) AS X
FROM
MyTable
) T2 ON T.KeyCol = T2.KeyCol
This is more concise but can't test to see if it works as expected
UPDATE T
SET SomeCol = X
FROM
(
SELECT
SomeCol, ROW_NUMBER() OVER (ORDER BY NEWID()) AS X
FROM
MyTable
) T
When you add TOP (1) (because you need to update first RndVal=0 record) and +1 (because otherwise your zero mark means nothing) to your update, things will start to move. But extremely slowly (around 40 seconds on my rather outdated laptop). This is because, as #myTable gets filled with generated random numbers, it becomes less and less probable to get missing numbers - you usually get duplicate, and have to start again.
UPDATE top (1) x
SET x.RndVal = FLOOR(RAND()*#rowsRequired) + 1
FROM #myTable x
WHERE x.RndVal = 0
Of course, #gbn has perfectly valid solution.
This is basically the same as the previous answer, but specific to your code:
;WITH CTE As
(
SELECT B_ID, C_ID, RndVal,
ROW_NUMBER() OVER(ORDER BY NewID()) As NewOrder
FROM #A
)
UPDATE CTE
SET RndVal = NewOrder
SELECT * FROM #A ORDER BY RndVal