I have a view defined like this:
CREATE VIEW [dbo].[PossiblyMatchingContracts] AS
SELECT
C.UniqueID,
CC.UniqueID AS PossiblyMatchingContracts
FROM [dbo].AllContracts AS C
INNER JOIN [dbo].AllContracts AS CC
ON C.SecondaryMatchCodeFB = CC.SecondaryMatchCodeFB
OR C.SecondaryMatchCodeLB = CC.SecondaryMatchCodeLB
OR C.SecondaryMatchCodeBB = CC.SecondaryMatchCodeBB
OR C.SecondaryMatchCodeLB = CC.SecondaryMatchCodeBB
OR C.SecondaryMatchCodeBB = CC.SecondaryMatchCodeLB
WHERE C.UniqueID NOT IN
(
SELECT UniqueID FROM [dbo].DefinitiveMatches
)
AND C.AssociatedUser IS NULL
AND C.UniqueID <> CC.UniqueID
Which is basically finding contracts where f.e. the first name and the birthday are matching. This works great. Now I want to add a synthetic attribute to each row with the value from only one source row.
Let me give you an example to make it clearer. Suppose I have the following table:
UniqueID | FirstName | LastName | Birthday
1 | Peter | Smith | 1980-11-04
2 | Peter | Gray | 1980-11-04
3 | Peter | Gray-Smith| 1980-11-04
4 | Frank | May | 1985-06-09
5 | Frank-Paul| May | 1985-06-09
6 | Gina | Ericson | 1950-11-04
The resulting view should look like this:
UniqueID | PossiblyMatchingContracts | SyntheticID
1 | 2 | PeterSmith1980-11-04
1 | 3 | PeterSmith1980-11-04
2 | 1 | PeterSmith1980-11-04
2 | 3 | PeterSmith1980-11-04
3 | 1 | PeterSmith1980-11-04
3 | 2 | PeterSmith1980-11-04
4 | 5 | FrankMay1985-06-09
5 | 4 | FrankMay1985-06-09
6 | NULL | NULL [or] GinaEricson1950-11-04
Notice that the SyntheticID column uses ONLY values from one of the matching source rows. It doesn't matter which one. I am exporting this view to another application and need to be able to identify each "match group" afterwards.
Is it clear what I mean? Any ideas how this could be done in sql?
Maybe it helps to elaborate a bit on the actual use case:
I am importing contracts from different systems. To account for the possibility of typos or people that have married but the last name was only updated in one system, I need to find so called 'possible matches'. Two or more contracts are considered a possible match if they contain the same birthday plus the same first, last or birth name. That implies, that if contract A matches contract B, contract B also matches contract A.
The target system uses multivalue reference attributes to store these relationships. The ultimate goal is to create user objects for these contracts. The catch first is, that the shall only be one user object for multiple matching contracts. Thus I'm creating these matches in the view. The second catch is, that the creation of user objects happens by workflows, which run parallel for each contract. To avoid creating multiple user objects for matching contracts, each workflow needs to check, if there is already a matching user object or another workflow, which is about to create said user object. Because the workflow engine is extremely slow compared to sql, the workflows should not repeat the whole matching test. So the idea is, to let the workflow check only for the 'syntheticID'.
I have solved it with a multi step approach:
Create the list of possible 1st level matches for each contract
Create the base groups list, assigning a different group for for
each contract (as if they were not related to anybody)
Iterate the matches list updating the group list when more contracts need to
be added to a group
Recursively build up the SyntheticID from final group list
Output results
First of all, let me explain what I have understood, so you can tell if my approach is correct or not.
1) matching propagates in "cascade"
I mean, if "Peter Smith" is grouped up with "Peter Gray", it means that all Smith and all Gray are related (if they have the same birth date) so Luke Smith can be in the same group of John Gray
2) I have not understood what you mean with "Birth Name"
You say contracts matches on "first, last or birth name", sorry, I'm italian, I thought birth name and first were the same, also in your data there is not such column. Maybe it is related to that dash symbol between names?
When FirstName is Frank-Paul it means it should match both Frank and Paul?
When LastName is Gray-Smith it means it should match both Gray and Smith?
In following code I have simply ignored this problem, but it could be handled if needed (I already did a try, breaking names, unpivoting them and treating as double match).
Step Zero: some declaration and prepare base data
declare #cli as table (UniqueID int primary key, FirstName varchar(20), LastName varchar(20), Birthday varchar(20))
declare #comb as table (id1 int, id2 int, done bit)
declare #grp as table (ix int identity primary key, grp int, id int, unique (grp,ix))
declare #str_id as table (grp int primary key, SyntheticID varchar(1000))
declare #id1 as int, #g int
;with
t as (
select *
from (values
(1 , 'Peter' , 'Smith' , '1980-11-04'),
(2 , 'Peter' , 'Gray' , '1980-11-04'),
(3 , 'Peter' , 'Gray-Smith', '1980-11-04'),
(4 , 'Frank' , 'May' , '1985-06-09'),
(5 , 'Frank-Paul', 'May' , '1985-06-09'),
(6 , 'Gina' , 'Ericson' , '1950-11-04')
) x (UniqueID , FirstName , LastName , Birthday)
)
insert into #cli
select * from t
Step One: Create the list of possible 1st level matches for each contract
;with
p as(select UniqueID, Birthday, FirstName, LastName from #cli),
m as (
select p.UniqueID UniqueID1, p.FirstName FirstName1, p.LastName LastName1, p.Birthday Birthday1, pp.UniqueID UniqueID2, pp.FirstName FirstName2, pp.LastName LastName2, pp.Birthday Birthday2
from p
join p pp on (pp.Birthday=p.Birthday) and (pp.FirstName = p.FirstName or pp.LastName = p.LastName)
where p.UniqueID<=pp.UniqueID
)
insert into #comb
select UniqueID1,UniqueID2,0
from m
Step Two: Create the base groups list
insert into #grp
select ROW_NUMBER() over(order by id1), id1 from #comb where id1=id2
Step Three: Iterate the matches list updating the group list
Only loop on contracts that have possible matches and updates only if needed
set #id1 = 0
while not(#id1 is null) begin
set #id1 = (select top 1 id1 from #comb where id1<>id2 and done=0)
if not(#id1 is null) begin
set #g = (select grp from #grp where id=#id1)
update g set grp= #g
from #grp g
inner join #comb c on g.id = c.id2
where c.id2<>#id1 and c.id1=#id1
and grp<>#g
update #comb set done=1 where id1=#id1
end
end
Step Four: Build up the SyntheticID
Recursively add ALL (distinct) first and last names of group to SyntheticID.
I used '_' as separator for birth date, first names and last names, and ',' as separator for the list of names to avoid conflicts.
;with
c as(
select c.*, g.grp
from #cli c
join #grp g on g.id = c.UniqueID
),
d as (
select *, row_number() over (partition by g order by t,s) n1, row_number() over (partition by g order by t desc,s desc) n2
from (
select distinct c.grp g, 1 t, FirstName s from c
union
select distinct c.grp, 2, LastName from c
) l
),
r as (
select d.*, cast(CONVERT(VARCHAR(10), t.Birthday, 112) + '_' + s as varchar(1000)) Names, cast(0 as bigint) i1, cast(0 as bigint) i2
from d
join #cli t on t.UniqueID=d.g
where n1=1
union all
select d.*, cast(r.names + IIF(r.t<>d.t,'_',',') + d.s as varchar(1000)), r.n1, r.n2
from d
join r on r.g = d.g and r.n1=d.n1-1
)
insert into #str_id
select g, Names
from r
where n2=1
Step Five: Output results
select c.UniqueID, case when id2=UniqueID then id1 else id2 end PossibleMatchingContract, s.SyntheticID
from #cli c
left join #comb cb on c.UniqueID in(id1,id2) and id1<>id2
left join #grp g on c.UniqueID = g.id
left join #str_id s on s.grp = g.grp
Here is the results
UniqueID PossibleMatchingContract SyntheticID
1 2 1980-11-04_Peter_Gray,Gray-Smith,Smith
1 3 1980-11-04_Peter_Gray,Gray-Smith,Smith
2 1 1980-11-04_Peter_Gray,Gray-Smith,Smith
2 3 1980-11-04_Peter_Gray,Gray-Smith,Smith
3 1 1980-11-04_Peter_Gray,Gray-Smith,Smith
3 2 1980-11-04_Peter_Gray,Gray-Smith,Smith
4 5 1985-06-09_Frank,Frank-Paul_May
5 4 1985-06-09_Frank,Frank-Paul_May
6 NULL 1950-11-04_Gina_Ericson
I think that in this way the resulting SyntheticID should also be "unique" for each group
This creates a synthetic value and is easy to change to suit your needs.
DECLARE #T TABLE (
UniqueID INT
,FirstName VARCHAR(200)
,LastName VARCHAR(200)
,Birthday DATE
)
INSERT INTO #T(UniqueID,FirstName,LastName,Birthday) SELECT 1,'Peter','Smith','1980-11-04'
INSERT INTO #T(UniqueID,FirstName,LastName,Birthday) SELECT 2,'Peter','Gray','1980-11-04'
INSERT INTO #T(UniqueID,FirstName,LastName,Birthday) SELECT 3,'Peter','Gray-Smith','1980-11-04'
INSERT INTO #T(UniqueID,FirstName,LastName,Birthday) SELECT 4,'Frank','May','1985-06-09'
INSERT INTO #T(UniqueID,FirstName,LastName,Birthday) SELECT 5,'Frank-Paul','May','1985-06-09'
INSERT INTO #T(UniqueID,FirstName,LastName,Birthday) SELECT 6,'Gina','Ericson','1950-11-04'
DECLARE #PossibleMatches TABLE (UniqueID INT,[PossibleMatch] INT,SynKey VARCHAR(2000)
)
INSERT INTO #PossibleMatches
SELECT t1.UniqueID [UniqueID],t2.UniqueID [Possible Matches],'Ln=' + t1.LastName + ' Fn=' + + t1.FirstName + ' DoB=' + CONVERT(VARCHAR,t1.Birthday,102) [SynKey]
FROM #T t1
INNER JOIN #T t2 ON t1.Birthday=t2.Birthday
AND t1.FirstName=t2.FirstName
AND t1.LastName=t2.LastName
AND t1.UniqueID<>t2.UniqueID
INSERT INTO #PossibleMatches
SELECT t1.UniqueID [UniqueID],t2.UniqueID [Possible Matches],'Fn=' + t1.FirstName + ' DoB=' + CONVERT(VARCHAR,t1.Birthday,102) [SynKey]
FROM #T t1
INNER JOIN #T t2 ON t1.Birthday=t2.Birthday
AND t1.FirstName=t2.FirstName
AND t1.UniqueID<>t2.UniqueID
INSERT INTO #PossibleMatches
SELECT t1.UniqueID,t2.UniqueID,'Ln=' + t1.LastName + ' DoB=' + CONVERT(VARCHAR,t1.Birthday,102) [SynKey]
FROM #T t1
INNER JOIN #T t2 ON t1.Birthday=t2.Birthday
AND t1.LastName=t2.LastName
AND t1.UniqueID<>t2.UniqueID
INSERT INTO #PossibleMatches
SELECT t1.UniqueID,pm.UniqueID,'Ln=' + t1.LastName + ' Fn=' + + t1.FirstName + ' DoB=' + CONVERT(VARCHAR,t1.Birthday,102) [SynKey]
FROM #T t1
LEFT JOIN #PossibleMatches pm on pm.UniqueID=t1.UniqueID
WHERE pm.UniqueID IS NULL
SELECT *
FROM #PossibleMatches
ORDER BY UniqueID,[PossibleMatch]
I think this will work for you
SELECT
C.UniqueID,
CC.UniqueID AS PossiblyMatchingContracts,
FIRST_VALUE(CC.FirstName+CC.LastName+CC.Birthday)
OVER (PARTITION BY C.UniqueID ORDER BY CC.UniqueID) as SyntheticID
FROM
[dbo].AllContracts AS C INNER JOIN
[dbo].AllContracts AS CC ON
C.SecondaryMatchCodeFB = CC.SecondaryMatchCodeFB OR
C.SecondaryMatchCodeLB = CC.SecondaryMatchCodeLB OR
C.SecondaryMatchCodeBB = CC.SecondaryMatchCodeBB OR
C.SecondaryMatchCodeLB = CC.SecondaryMatchCodeBB OR
C.SecondaryMatchCodeBB = CC.SecondaryMatchCodeLB
WHERE
C.UniqueID NOT IN(
SELECT UniqueID FROM [dbo].DefinitiveMatches)
AND C.AssociatedUser IS NULL
You can try this:
SELECT
C.UniqueID,
CC.UniqueID AS PossiblyMatchingContracts,
FIRST_VALUE(CC.FirstName+CC.LastName+CC.Birthday)
OVER (PARTITION BY C.UniqueID ORDER BY CC.UniqueID) as SyntheticID
FROM
[dbo].AllContracts AS C
INNER JOIN
[dbo].AllContracts AS CC
ON
C.SecondaryMatchCodeFB = CC.SecondaryMatchCodeFB
OR
C.SecondaryMatchCodeLB = CC.SecondaryMatchCodeLB
OR
C.SecondaryMatchCodeBB = CC.SecondaryMatchCodeBB
OR
C.SecondaryMatchCodeLB = CC.SecondaryMatchCodeBB
OR
C.SecondaryMatchCodeBB = CC.SecondaryMatchCodeLB
WHERE
C.UniqueID NOT IN
(
SELECT UniqueID FROM [dbo].DefinitiveMatches
)
AND
C.AssociatedUser IS NULL
This will generate one extra row (because we left out C.UniqueID <> CC.UniqueID) but will give you the good souluton.
Following an example with some example data extracted from your original post. The idea: Generate all SyntheticID in a CTE, query all records with a "PossibleMatch" and Union it with all records which are not yet included:
DECLARE #t TABLE(
UniqueID int
,FirstName nvarchar(20)
,LastName nvarchar(20)
,Birthday datetime
)
INSERT INTO #t VALUES (1, 'Peter', 'Smith', '1980-11-04');
INSERT INTO #t VALUES (2, 'Peter', 'Gray', '1980-11-04');
INSERT INTO #t VALUES (3, 'Peter', 'Gray-Smith', '1980-11-04');
INSERT INTO #t VALUES (4, 'Frank', 'May', '1985-06-09');
INSERT INTO #t VALUES (5, 'Frank-Paul', 'May', '1985-06-09');
INSERT INTO #t VALUES (6, 'Gina', 'Ericson', '1950-11-04');
WITH ctePrep AS(
SELECT UniqueID, FirstName, LastName, BirthDay,
ROW_NUMBER() OVER (PARTITION BY FirstName, BirthDay ORDER BY FirstName, BirthDay) AS k,
FirstName+LastName+CONVERT(nvarchar(10), Birthday, 126) AS SyntheticID
FROM #t
),
cteKeys AS(
SELECT FirstName, BirthDay, SyntheticID
FROM ctePrep
WHERE k = 1
),
cteFiltered AS(
SELECT
C.UniqueID,
CC.UniqueID AS PossiblyMatchingContracts,
keys.SyntheticID
FROM #t AS C
JOIN #t AS CC ON C.FirstName = CC.FirstName
AND C.Birthday = CC.Birthday
JOIN cteKeys AS keys ON keys.FirstName = c.FirstName
AND keys.Birthday = c.Birthday
WHERE C.UniqueID <> CC.UniqueID
)
SELECT UniqueID, PossiblyMatchingContracts, SyntheticID
FROM cteFiltered
UNION ALL
SELECT UniqueID, NULL, FirstName+LastName+CONVERT(nvarchar(10), Birthday, 126) AS SyntheticID
FROM #t
WHERE UniqueID NOT IN (SELECT UniqueID FROM cteFiltered)
Hope this helps. The result looked OK to me:
UniqueID PossiblyMatchingContracts SyntheticID
---------------------------------------------------------------
2 1 PeterSmith1980-11-04
3 1 PeterSmith1980-11-04
1 2 PeterSmith1980-11-04
3 2 PeterSmith1980-11-04
1 3 PeterSmith1980-11-04
2 3 PeterSmith1980-11-04
4 NULL FrankMay1985-06-09
5 NULL Frank-PaulMay1985-06-09
6 NULL GinaEricson1950-11-04
Tested in SSMS, it works perfect. :)
--create table structure
create table #temp
(
uniqueID int,
firstname varchar(15),
lastname varchar(15),
birthday date
)
--insert data into the table
insert #temp
select 1, 'peter','smith','1980-11-04'
union all
select 2, 'peter','gray','1980-11-04'
union all
select 3, 'peter','gray-smith','1980-11-04'
union all
select 4, 'frank','may','1985-06-09'
union all
select 5, 'frank-paul','may','1985-06-09'
union all
select 6, 'gina','ericson','1950-11-04'
select * from #temp
--solution is as below
select ab.uniqueID
, PossiblyMatchingContracts
, c.firstname+c.lastname+cast(c.birthday as varchar) as synID
from
(
select a.uniqueID
, case
when a.uniqueID < min(b.uniqueID)over(partition by a.uniqueid)
then a.uniqueID
else min(b.uniqueID)over(partition by a.uniqueid)
end as SmallestID
, b.uniqueID as PossiblyMatchingContracts
from #temp a
left join #temp b
on (a.firstname = b.firstname OR a.lastname = b.lastname) AND a.birthday = b.birthday AND a.uniqueid <> b.uniqueID
) as ab
left join #temp c
on ab.SmallestID = c.uniqueID
Result capture is attached below:
Say we have following table (a VIEW in your case):
UniqueID PossiblyMatchingContracts SyntheticID
1 2 G1
1 3 G2
2 1 G3
2 3 G4
3 1 G4
3 4 G6
4 5 G7
5 4 G8
6 NULL G9
In your case you can set initial SyntheticID as a string like PeterSmith1980-11-04 using UniqueID for each line. Here is a recursive CTE query it divides all lines to unconnected groups and select MAX(SyntheticId) in the current group as a new SyntheticID for all lines in this group.
WITH CTE AS
(
SELECT CAST(','+CAST(UniqueID AS Varchar(100)) +','+ CAST(PossiblyMatchingContracts as Varchar(100))+',' as Varchar(MAX)) as GroupCont,
SyntheticID
FROM PossiblyMatchingContracts
UNION ALL
SELECT CAST(GroupCont+CAST(UniqueID AS Varchar(100)) +','+ CAST(PossiblyMatchingContracts as Varchar(100))+',' AS Varchar(MAX)) as GroupCont,
pm.SyntheticID
FROM CTE
JOIN PossiblyMatchingContracts as pm
ON
(
CTE.GroupCont LIKE '%,'+CAST(pm.UniqueID AS Varchar(100))+',%'
OR
CTE.GroupCont LIKE '%,'+CAST(pm.PossiblyMatchingContracts AS Varchar(100))+',%'
)
AND NOT
(
CTE.GroupCont LIKE '%,'+CAST(pm.UniqueID AS Varchar(100))+',%'
AND
CTE.GroupCont LIKE '%,'+CAST(pm.PossiblyMatchingContracts AS Varchar(100))+',%'
)
)
SELECT pm.UniqueID,
pm.PossiblyMatchingContracts,
ISNULL(
(SELECT MAX(SyntheticID) FROM CTE WHERE
(
CTE.GroupCont LIKE '%,'+CAST(pm.UniqueID AS Varchar(100))+',%'
OR
CTE.GroupCont LIKE '%,'+CAST(pm.PossiblyMatchingContracts AS Varchar(100))+',%'
))
,pm.SyntheticID) as SyntheticID
FROM PossiblyMatchingContracts pm
I've a basic SQL table with a simple heirarchial connection between each rows. That is there is a ParentID for Every rows and using that its connecting with another row. Its as follows
AccountID | AccountName | ParentID
---------------------------------------
1 Mathew 0
2 Philip 1
3 John 2
4 Susan 2
5 Anita 1
6 Aimy 1
7 Elsa 3
8 Anna 7
.............................
.................................
45 Kristoff 8
Hope the structure is clear
But my requirement of listng these is a little weird. That is when we pass an AccountID, it should list all its parents and siblings and siblings childrens. But it never list any child of that AccountID to any level. I can explain that in little more detail with a picture. Sorry for the clarity of the picture.. mine is an old phone cam..
When we pass the AccountID 4, it should list all Parents and its siblings, but it should not list 4,6,7,8,9,10. That means that account and any of it childrens should be avoid in the result (Based on the picture tree elements). Hope the explanation is clear.
If I've got it right and you need to output whole table except 4 and all of it's descendants then try this recursive query:
WITH CT AS
(
SELECT * FROM T WHERE AccountID=4
UNION ALL
SELECT T.* FROM T
JOIN CT ON T.ParentID = CT.AccountId
)
SELECT * FROM T WHERE AccountID
NOT IN (SELECT AccountID FROM CT)
SQLFiddle demo
Answering to the question in the comment:
So it will not traverse to the top. It only traverse to specified
account. For example if I pass 4 as first parameter and 2 as second
parameter, the result should be these values 2,5,11,12
You should start from the ID=2 and travel to the bottom exclude ID=4 so you cut whole subtree after ID=4:
WITH CT AS
(
SELECT * FROM T WHERE AccountID=2
UNION ALL
SELECT T.* FROM T
JOIN CT ON T.ParentID = CT.AccountId
WHERE T.AccountId<>4
)
SELECT * FROM CT
Try this:
;with cte as
(select accountid,parentid, 0 as level from tbl
where parentid = 0
union all
select t.accountid,t.parentid,(level+1) from
cte c inner join tbl t on c.accountid= t.parentid
)
select * from cte
where level < (select level from cte where accountid = #accountid)
When you pass in the parameter #accountid this will return the accountid values of all nodes on levels before that of the parameter.
If you want to return everything on the same level as input except input itself, you can change the where clause to;
where level <=(select level from cte where accountid= #accountid )
and accountid <> #accountid
In your example, if #accountid = 4, this will return the values 1,2,3 (ancestors) as well as 5,13,14 (siblings).
Does this return what you are after?
declare #AccountID int
set #AccountID = 4
;with parents
as (
select AccountID, AccountName, ParentID
from Account
where AccountID = (select ParentID from Account Where AccountID = #AccountID)
union all
select A.AccountID, A.AccountName, A.ParentID
from Account as A
join parents as P
on P.ParentID = A.AccountID
),
children
as (
select AccountID, AccountName, ParentID
from parents
union all
select A.AccountID, A.AccountName, A.ParentID
from Account as A
join children as C
on C.AccountID = A.ParentID
where A.AccountID <> #AccountID
)
select distinct AccountID, AccountName, ParentID
from children
order by AccountID
For me it sounds like you want to go up in the tree. So considering this test data
DECLARE #tbl TABLE(AccountID INT,AccountName VARCHAR(100),ParentID INT)
INSERT INTO #tbl
VALUES
(1,'Mathew',0),
(2,'Philip',1),
(3,'John',2),
(4,'Susan',2),
(5,'Anita',1),
(6,'Aimy',1),
(7,'Elsa',3),
(8,'Anna',7)
The I would write a query like this:
DECLARE #AcountID INT=4
;WITH CTE
AS
(
SELECT
tbl.AccountID,
tbl.AccountName,
tbl.ParentID
FROM
#tbl AS tbl
WHERE
tbl.AccountID=#AcountID
UNION ALL
SELECT
tbl.AccountID,
tbl.AccountName,
tbl.ParentID
FROM
#tbl AS tbl
JOIN CTE
ON CTE.ParentID=tbl.AccountID
)
SELECT
*
FROM
CTE
WHERE
NOT CTE.AccountID=#AcountID
This will return a result like this:
2 Philip 1
1 Mathew 0
Is it possible to COUNT the number of times a value occurs in a table, however, use the count of 1 if the value appears more than once for each id.
Take the below table as an example. We want to see if either {5,6} occurred for p_id. If more than 1 occurrence of {5,6} is found, treat it as 1. For eg. p_id 1, the total count is 1.
p_id status
1 5
1 6
1 2
2 5
2 5
3 4
3 2
4 6
4 2
4 5
..transforms to..
p_id count
1 1
2 1
3 0
4 1
COUNT(CASE status IN (5,6) THEN 1 END) does an overall count.
Use the CASE...WHEN... as follows:
SELECT a.id, ISNULL(b.cnt, 0)
FROM
(
SELECT DISTINCT id FROM tab
) a
LEFT JOIN
(
SELECT id, CASE COUNT(*) WHEN 1 THEN 0 ELSE 1 END 'cnt'
FROM tab WHERE val in (5, 6) GROUP BY id
) b
ON a.id = b.id
SQLFiddle
This solution provides a quick setup and a simple two-step explanation of how I do this, using your example. The second query provides the desired result:
CREATE TABLE #temp (p_id INT, [status] INT);
INSERT #temp VALUES (1,5);
INSERT #temp VALUES (1,6);
INSERT #temp VALUES (1,2);
INSERT #temp VALUES (2,5);
INSERT #temp VALUES (2,5);
INSERT #temp VALUES (3,4);
INSERT #temp VALUES (3,2);
INSERT #temp VALUES (4,6);
INSERT #temp VALUES (4,2);
INSERT #temp VALUES (4,5);
-- Simple two-step tutorial
-- First, group by p_id so that all p_id's will be shown
-- run this to see...
SELECT A.p_id
FROM #temp A
GROUP BY A.p_id;
-- Now expand your query
-- Next, for each p_id row found, perform sub-query to see if 1 or more exist with status=5 or 6
SELECT A.p_id
,CASE WHEN EXISTS(SELECT 1 FROM #temp B WHERE B.p_id=A.p_id AND [status] IN (5,6)) THEN 1 ELSE 0 END AS [Count]
FROM #temp A
GROUP BY A.p_id;
Use the SIGN() function. It is exactly what you are looking for.
SELECT
[p_id],
SIGN(COUNT(CASE WHEN [status] IN (5,6) THEN 1 END)) AS [count]
FROM #temp
GROUP BY p_id
You can translate 5,6 = 1 and rest to 0 then do max()
with cte as (
select p_id, case when status in (5,6) then 1 else 0 end status
from FROM #tem)
select p_id, max(status) status
from cte
group by p_id
Given the following tables:
table objects
id Name rating
1 Megan 9
2 Irina 10
3 Vanessa 7
4 Samantha 9
5 Roxanne 1
6 Sonia 8
swap table
id swap_proposalid counterpartyid
1 4 2
2 3 2
Everyone wants the ten. I would like to make a list for Irina of possible swaps where id 4 and 3 don't appear because the propositions are already there.
output1
id Name rating
1 Megan 9
5 Roxanne 1
6 Sonia 8
Thanks
This should do the trick:
SELECT o.id, o.Name, o.rating
FROM objects o
LEFT JOIN swap s on o.id = s.swap_proposalid
WHERE s.id IS NULL
AND o.Name != 'Irina'
This works
SELECT mt2.ID, mt2.Name, mt2.Rating
FROM [MyTable] mt2 -- Other Candidates
, [MyTable] mt1 -- Candidate / Subject (Irina)
WHERE mt2.ID NOT IN
(
SELECT st.swap_proposalid
FROM SwapTable st
WHERE
st.counterpartyid = mt1.ID
)
AND mt1.ID <> mt2.ID -- Don't match Irina with Irina
AND mt1.Name = 'Irina' -- Find other swaps for Irina
-- Test Data
CREATE TABLE MyTable
(
ID INT,
Name VARCHAR(100),
Rating INT
)
GO
CREATE TABLE SwapTable
(
ID INT,
swap_proposalid INT,
counterpartyid INT
)
GO
INSERT INTO MyTable VALUES(1 ,'Megan', 9)
INSERT INTO MyTable VALUES(2 ,'Irina', 10)
INSERT INTO MyTable VALUES(3 ,'Vanessa', 7)
INSERT INTO MyTable VALUES(4 ,'Samantha', 9)
INSERT INTO MyTable VALUES(5 ,'Roxanne', 1)
INSERT INTO MyTable VALUES(6 ,'Sonia', 8)
INSERT INTO SwapTable(ID, swap_proposalid, counterpartyid)
VALUES (1, 4, 2)
INSERT INTO SwapTable(ID, swap_proposalid, counterpartyid)
VALUES (1, 3, 2)
Guessing that the logic involves identifying the objects EXCEPT the highest rated object EXCEPT propositions with the highest rated object e.g. (using sample DDL and data kindly posted by #nonnb):
WITH ObjectHighestRated
AS
(
SELECT ID
FROM MyTable
WHERE Rating = (
SELECT MAX(T.Rating)
FROM MyTable T
)
),
PropositionsForHighestRated
AS
(
SELECT swap_proposalid AS ID
FROM SwapTable
WHERE counterpartyid IN (SELECT ID FROM ObjectHighestRated)
),
CandidateSwappersForHighestRated
AS
(
SELECT ID
FROM MyTable
EXCEPT
SELECT ID
FROM ObjectHighestRated
EXCEPT
SELECT ID
FROM PropositionsForHighestRated
)
SELECT *
FROM MyTable
WHERE ID IN (SELECT ID FROM CandidateSwappersForHighestRated);
I have a table for contents on a page. The page is divided into sections.
I want to get the last version for each page-section.
Id (int)
Version (int)
SectionID
Id Version SectionID Content
1 1 1 AAA
2 2 1 BBB
3 1 2 CCC
4 2 2 DDD
5 3 2 EEE
I want to get:
Id Version SectionID Content
2 2 1 BBB
5 3 2 EEE
You could use an exclusive self join:
select last.*
from YourTable last
left join
YourTable new
on new.SectionID = last.SectionID
and new.Version > last.Version
where new.Id is null
The where statement basically says: where there is no newer version of this row.
Slightly more readable, but often slower, is a not exists condition:
select *
from YourTable yt
where not exists
(
select *
from YourTable yt2
where yt2.SectionID = yt.SectionID
and yt2.Version > yt.Version
)
Example table definition:
declare #t table(Id int, [Version] int, [SectionID] int, Content varchar(50))
insert into #t values (1,1,1,'AAA');
insert into #t values (2,2,1,'BBB');
insert into #t values (3,1,2,'CCC');
insert into #t values (4,2,2,'DDD');
insert into #t values (5,3,2,'EEE');
Working solution:
select A.Id, A.[Version], A.SectionID, A.Content
from #t as A
join (
select max(C.[Version]) [Version], C.SectionID
from #t C
group by C.SectionID
) as B on A.[Version] = B.[Version] and A.SectionID = B.SectionID
order by A.SectionID
A simpler and more readeable solution:
select A.Id, A.[Version], A.SectionID, A.Content
from #t as A
where A.[Version] = (
select max(B.[Version])
from #t B
where A.SectionID = B.SectionID
)
I just saw that there was a very similar question for Oracle with an accepted answer based on performance.
Maybe if your table is big, an performance is an issue you can give it a try to see if SQL server also performs better with this:
select Id, Version, SectionID, Content
from (
select Id, Version, SectionID, Content,
max(Version) over (partition by SectionID) max_Version
from #t
) A
where Version = max_Version