I want a count of all child and sub child of where a particular parent exists.
I have this data:
| Id | Parent
+-----------------------------------------+-------------------------------------+
| 736F8C6A-D58D-442E-BE2E-3B9F0595C58B | NULL |
| CA828BBA-6657-46FC-BA26-7ED8C7FB220C | 736F8C6A-D58D-442E-BE2E-3B9F0595C58B|
| 2DB8A8F9-9F29-4F3A-907F-A6ACEDE12859 | 736F8C6A-D58D-442E-BE2E-3B9F0595C58B|
If I pass 736F8C6A-D58D-442E-BE2E-3B9F0595C58B, then it should return the total count of its children and grandchildren - that is a total of 2.
Any suggestions?
First, i used the following query to create the temp table
CREATE TABLE #TBLTEMP(ID int, ParentID int)
INSERT INTO #TBLTEMP(ID,ParentID)
VALUES(1,NULL)
,(2,1)
,(3,2)
,(4,2)
,(5,3)
,(6,NULL)
,(7,6)
,(8,NULL)
,(9,NULL)
Then i used the following query to retrieve childs count
WITH CTE_1(ParentID) AS(
SELECT ParentID FROM #TBLTEMP T1
UNION ALL
SELECT T2.ParentID FROM CTE_1 c
INNER JOIN #TBLTEMP T2 ON c.ParentID = T2.ID
WHERE T2.ParentID > 0
), CTE_2 AS ( SELECT ID , 0 as cnt FROM #TBLTEMP T3 WHERE NOT EXISTS (SELECT 1 FROM CTE_1 c2 where c2.ParentID = T3.ID))
SELECT ParentID, count(*) as cnt
FROM CTE_1
WHERE ParentID IS NOT NULL
GROUP BY ParentID
UNION
SELECT ID as ParentID, cnt FROM CTE_2
ORDER BY ParentID
The result is:
Reference
Recursive CTE to find Total for all children
Update 1
To getcount for a specific ID:
WITH CTE_1(ParentID) AS(
SELECT ParentID FROM #TBLTEMP T1
UNION ALL
SELECT T2.ParentID FROM CTE_1 c
INNER JOIN #TBLTEMP T2 ON c.ParentID = T2.ID
WHERE T2.ParentID > 0
), CTE_2 AS ( SELECT ID , 0 as cnt FROM #TBLTEMP T3 WHERE NOT EXISTS (SELECT 1 FROM CTE_1 c2 where c2.ParentID = T3.ID)), CTE_3 AS(
SELECT ParentID, count(*) as cnt
FROM CTE_1
WHERE ParentID IS NOT NULL
GROUP BY ParentID
UNION
SELECT ID as ParentID, cnt FROM CTE_2)
SELECT cnt FROM CTE_3 WHERE ParentID = 1
Related
I got a very simple table, but I'm struggling with CTE:
ID | Parent | Name
---+--------+---------
1 | NULL | Root
2 | 1 | Child1
3 | 2 | Child2
I'd like to receive a result like this:
Element | Root
--------+------
Root | Root
Child1 | Root
Child2 | Root
My CTE is something like this...
WITH cte AS
(
SELECT a.id, a.parent, a.name, 1 as lvl
FROM table1 a
UNION ALL
-- Perform the recursive join
SELECT a.id, a.parent, a.name, Lvl+1 AS Lvl
FROM table1 a
INNER JOIN cte pa ON cte.parent = a.id
)
SELECT *
FROM cte
Now I would aggregate (max) and (self)join but it seems kinda bad/wrong.
This is a little complicated, because you are traversing ids but in the end, you just want names. The following handles this by looking up the names after the recursive CTE has found the root ids:
with cte as (
select id, parent, name, 1 as lev
from t
union all
select cte.id, t.parent, cte.name, lev + 1
from cte join
t
on t.id = cte.parent
where t.parent is not null
)
select top (1) with ties cte.name, coalesce(tparent.name, cte.name) as root
from cte left join
t tparent
on tparent.id = cte.parent
order by row_number() over (partition by cte.id order by cte.lev desc)
Here is a db<>fiddle.
Try
with cte as (
select id, parent, name, name as root
from t
where parent is null
union all
select t.id, t.parent, t.name, cte.root
from cte
join t on t.parent = cte.id
)
select name, root
from cte
I am trying to build a deep recursive self-join query. Having the table like:
Id | ParentId
1 | NULL
2 | 1
3 | 1
4 | 2
5 | 3
6 | 8
7 | 9
For Id 1 my query should be fetching 1,2,3,4,5 since they are either the children of 1 or children of the children of 1. In the given example 6 and 7 should not be included in the query result.
I tried using CTE but I am getting tons of duplicates:
WITH CTE AS (
SELECT Id, ParentId
FROM dbo.Table
WHERE ParentId IS NULL
UNION ALL
SELECT t.Id, t.ParentId
FROM dbo.Table t
INNER JOIN CTE c ON t.ParentId = c.Id
)
SELECT * FROM CTE
Ideas?
You can try to use DISTINCT to filter duplicate rows.
;WITH CTE AS (
SELECT Id, ParentId
FROM T
WHERE ParentId IS NULL
UNION ALL
SELECT t.Id, t.ParentId
FROM T
INNER JOIN CTE c ON t.ParentId = c.Id
)
SELECT DISTINCT Id, ParentId
FROM CTE
Try the following query with CTE where you can set parentId by #parentID:
DECLARE #parentID INT = 1
;WITH cte AS
(
SELECT
t.ID
, t.ParentId
FROM #table t
),
cteParent AS
(
SELECT
t.ID
, t.ParentId
FROM #table t
WHERE t.ParentId IN (SELECT t1.ID FROM #table t1 WHERE T1.ParentId = #parentID)
)
SELECT
DISTINCT c1.ID
, c1.ParentId
FROM cte c1
INNER JOIN cte c2 ON c2.ParentId = c1.ID
UNION ALL
SELECT *
FROM cteParent
And the sample data:
DECLARE #table TABLE
(
ID INT
, ParentId INT
)
INSERT INTO #table
(
ID,
ParentId
)
VALUES
(1, NULL )
, (2, 1 )
, (3, 1 )
, (4, 2 )
, (5, 3 )
, (6, 8 )
, (7, 9 )
OUTPUT:
ID ParentId
1 NULL
2 1
3 1
4 2
5 3
I don't see duplicates.
Your code returns the following on the data you provided:
Id ParentId
1
2 1
3 1
5 3
4 2
which is what you want.
Here is a db<>fiddle.
Here is the code:
WITH t as (
SELECT *
FROM (VALUES (1, NULL), (2, 1), (3, 1), (4, 2), (5, 3), (6, 8), (7, 9)
) v(id, parentId)
),
CTE AS (
SELECT Id, ParentId
FROM t
WHERE ParentId IS NULL
UNION ALL
SELECT t.Id, t.ParentId
FROM t
INNER JOIN CTE c ON t.ParentId = c.Id
)
SELECT *
FROM CTE;
If you are getting duplicates in your actual result set, then you presumably have duplicates in your original table. I would recommend removing them before doing the recursive logic:
with t as (
select distinct id, parentid
from <your query>
),
. . .
Then run the recursive logic.
Try this sql script which result Parent Child Hierarchy
;WITH CTE(Id , ParentId)
AS
(
SELECT 1 , NULL UNION ALL
SELECT 2 , 1 UNION ALL
SELECT 3 , 1 UNION ALL
SELECT 4 , 2 UNION ALL
SELECT 5 , 3 UNION ALL
SELECT 6 , 8 UNION ALL
SELECT 7 , 9
)
,Cte2
AS
(
SELECT Id ,
ParentId ,
CAST('\'+ CAST(Id AS VARCHAR(MAX))AS VARCHAR(MAX)) AS [Hierarchy]
FROM CTE
WHERE ParentId IS NULL
UNION ALL
SELECT c1.Id ,
c1.ParentId ,
[Hierarchy]+'\'+ CAST(c1.Id AS VARCHAR(MAX)) AS [Hierarchy]
FROM Cte2 c2
INNER JOIN CTE c1
ON c1.ParentId = c2.Id
)
SELECT Id,
RIGHT([Hierarchy],LEN([Hierarchy])-1) AS ParentChildHierarchy
FROM Cte2
GO
Result
Id ParentChildHierarchy
-------------------------
1 1
2 1\2
3 1\3
5 1\3\5
4 1\2\4
This query will help you
CREATE TABLE #table( ID INT, ParentId INT )
INSERT INTO #table(ID,ParentId)
VALUES (1, NULL ), (2, 1 ), (3, 1 ), (4, 2 ), (5, 3 ), (6, 8 ), (7, 9 )
;WITH CTE AS (
SELECT ID FROM #table WHERE PARENTID IS NULL
UNION ALL
SELECT T.ID FROM #table T
INNER JOIN #table T1 ON T.PARENTID =T1.ID
) SELECT * FROM CTE
I have two tables that I want to join together such that all foreign rows are returned and the primary table's rows are not duplicated. For example:
T1
pk code value
1 One 100
2 Two 200
T2
fk value
1 10
1 15
1 30
2 25
I want all records of T2 without the T1 records duplicating, so the result set I want to look like this:
T2.fk T1.code T1.value T2.value
1 One 100 10
1 NULL NULL 15
1 NULL NULL 30
2 Two 200 25
Is there a SQL Server join method for achieving that?
You need to rank your rows in T2 and do a left join including rank as a join condition:
with cte as(select *, row_number() over(partition by fk order by value) as rn from T2)
select c.fk, t.code, t.value, c.value
from cte c
left join T1 t on c.fk = t.pk and c.rn = 1
Here is the full example:
DECLARE #t1 TABLE
(
pk INT ,
code VARCHAR(MAX) ,
value INT
)
INSERT INTO #t1
VALUES ( 1, 'One', 100 ),
( 2, 'Two', 200 )
DECLARE #t2 TABLE ( fk INT, value INT )
INSERT INTO #t2
VALUES ( 1, 10 ),
( 1, 15 ),
( 1, 30 ),
( 2, 25 );
WITH cte
AS ( SELECT * ,
ROW_NUMBER() OVER ( PARTITION BY fk ORDER BY value ) AS rn
FROM #t2
)
SELECT c.fk ,
t.code ,
t.value ,
c.value
FROM cte c
LEFT JOIN #t1 t ON c.fk = t.pk
AND c.rn = 1
Try this:
select T2.fk,
CASE
WHEN (SELECT COUNT(*) FROM t2 tother WHERE tother.fk = t2.fk
AND tother.value > t2.value) > 0 THEN NULL ELSE t1.code
END,
CASE
WHEN (SELECT COUNT(*) FROM t2 tother WHERE tother.fk = t2.fk
AND tother.value > t2.value) > 0 THEN NULL ELSE t1.value
END,T2.value
from t2
join t1
on t2.fk = t1.pk
DECLARE #t1 TABLE (pk int,code varchar(10),value int)
DECLARE #t2 TABLE (fk int,value int)
INSERT INTO #t1
SELECT 1,'one',100
UNION
SELECT 2,'two',200
INSERT INTO #t2
SELECT 1,10
UNION SELECT 1,15 UNION SELECT 1,30 UNION SELECT 2,25
;WITH cte AS(
SELECT t2.fk,t2.value t2val,t1.pk,t1.code,t1.value t1val,ROW_NUMBER() OVER(PARTITION BY fk ORDER BY fk) rno FROM #t2 t2 LEFT JOIN #t1 t1 on t2.fk=t1.pk)
SELECT fk,code=(CASE WHEN rno=1 THEN code ELSE null END),t1val=(CASE WHEN rno=1 THEN t1val ELSE NULL END),t2val FROM cte
output
fk code t1val t2val
1 one 100 10
1 NULL NULL 15
1 NULL NULL 30
2 two 200 25
I have a table that looks like this:
ID SuppressionTypeID PersonID
------------------------------
1 1 123
2 1 456
3 2 456
I want to get a rolling count (distinct people) rather than a normal group by count.
e.g. not this:
SuppressionTypeID Count
---------------------------
1 2
2 1
This:
SuppressionTypeID RecordsLost
----------------------------------
1 2
2 0
The latter being zero as we lost person 456 on suppresiontypeid 1.
Thanks in advance.
You may need to use a temporary table or a table variable as shown below
DECLARE #t TABLE (
ID INT
,SuppressionTypeID INT
,PersonID INT
)
INSERT INTO #t
SELECT 1
,1
,123
UNION ALL
SELECT 2
,1
,456
UNION ALL
SELECT 3
,2
,456
DECLARE #t1 TABLE (
ID INT
,SuppressionTypeID INT
,PersonID INT
,firstid INT
)
INSERT INTO #t1
SELECT *
,NULL
FROM #t
UPDATE t1
SET t1.firstid = t2.firstid
FROM #t1 AS t1
INNER JOIN (
SELECT personid
,min(SuppressionTypeID) AS firstid
FROM #t1
GROUP BY personid
) AS t2 ON t1.PersonID = t2.PersonID
SELECT coalesce(t2.firstid, t1.SuppressionTypeID) AS SuppressionTypeID
,count(DISTINCT t2.personid) AS count
FROM #t1 AS t1
LEFT JOIN #t1 AS t2 ON t1.personid = t2.personid
AND t1.SuppressionTypeID = t2.firstid
GROUP BY coalesce(t2.firstid, t1.SuppressionTypeID)
The result is
SuppressionTypeID count
----------------- -----------
1 2
2 0
You can try;
with tmp_tbl as (
select
x.SuppressionTypeID, count(x.PersonID) as RecordsLost
from (
select
min(SuppressionTypeID) as SuppressionTypeID,
PersonID
from tbl
group by PersonID
) as x
group by x.PersonID
order by x.SuppressionTypeID
)
select
distict t.SuppressionTypeID, coalesce(tmp.RecordsLost, 0) as RecordsLost
from tbl t
left join tmp_tbl tmp on tmp.SuppressionTypeID = t.SuppressionTypeID
Let's say I have a database schema like this:
RowId ParentId Name
------ ---------- ------
1 NULL Level1
2 NULL Level2
3 1 Leaf1
4 1 Leaf2
5 2 Leaf1
6 3 LeafX
Basically, the tree would look as such:
Level1
Leaf1
LeafX
Leaf2
Level2
Leaf1
I need to extract all ancestor LEVEL of LeafX in the most efficient and dynamic way.
So it will output: Leaf1, Leaf2, and Leaf1 (of Level2)
How do I do this in T-SQL? Thanks
This will give you the result you want.
;with C as
(
select T.rowid,
T.parentid,
T.name,
1 as Lvl
from YourTable as T
where T.parentid is null
union all
select T.rowid,
T.parentid,
T.name,
C.Lvl + 1
from YourTable as T
inner join C
on T.parentid = C.rowid
)
select *
from C
where C.Lvl = (
select C.lvl-1
from C
where C.name = 'LeafX'
)
Update
And this might be faster for you. You have to test on your data.
declare #Level int;
with C as
(
select T.rowid,
T.parentid
from #t as T
where T.name = 'LeafX'
union all
select T.rowid,
T.parentid
from #t as T
inner join C
on T.rowid = C.parentid
)
select #Level = count(*) - 1
from C;
with C as
(
select T.rowid,
T.parentid,
T.name,
1 as Lvl
from #t as T
where T.parentid is null
union all
select T.rowid,
T.parentid,
T.name,
C.Lvl + 1
from #t as T
inner join C
on T.parentid = C.rowid
where C.Lvl < #Level
)
select *
from C
where C.Lvl = #Level;
There's a few methods to do that. My favourite is to create special table Trees_Parents, where you will store every parent for evere node.
So if have structure like that
RowId ParentId Name
------ ---------- ------
1 NULL Level1
2 NULL Level2
3 1 Leaf1
4 1 Leaf2
5 2 Leaf1
6 3 LeafX
your Trees_Parents table will looks like
RowId ParentId
------ ----------
1 1
2 2
3 3
3 1
4 4
4 1
5 5
5 2
6 6
6 1
6 3
then when you need to retrieve all children you just write
select RowID from Trees_Parents where ParentId = 1
I'm storing row self in this table to avoid unions, if you don't need it you can write
select RowID from Trees_Parents where ParentId = 1 and ParentId <> RowId
And for all parents you'll write
select ParentId from Trees_Parents where RowId = 6 and ParentId <> RowId
You can also store Table_Name in table Trees_Parents so you can use it for different tables
Another way is to write recursive WITH clause, but if your tree is big and it's not changing frequently I think it's better to store parents data in additional table
Well you can use recursive solution. You need to get all nodes with Depth = Depth of your node - 1
declare #Temp table (RowId int, ParentId int, Name nvarchar(128))
insert into #Temp
select 1, null, 'Level1' union all
select 2, null, 'Level2' union all
select 3, 1, 'Leaf1' union all
select 4, 1, 'Leaf2' union all
select 5, 2, 'Leaf3' union all
select 6, 3, 'LeafX';
with Parents
as
(
select T.RowId, 0 as Depth from #Temp as T where T.ParentId is null
union all
select T.RowId, P.Depth + 1
from Parents as P
inner join #Temp as T on T.ParentId = P.RowId
)
select T.Name
from Parents as P
outer apply (select TT.Depth from Parents as TT where TT.RowId = 6) as CALC
left outer join #Temp as T on T.RowId = P.RowId
where P.Depth = CALC.Depth - 1
declare #t table(rowid int, parentid int, name varchar(10))
insert #t values(1,NULL,'Level1')
insert #t values(2,NULL,'Level2')
insert #t values(3,1,'Leaf1')
insert #t values(4,1,'Leaf2')
insert #t values(5,2,'Leaf1')
insert #t values(6,3,'LeafX')
;with a as
(
select rowid, parentid, 0 level from #t where name = 'leafx'
union all
select t.rowid, t.parentid, level + 1 from #t t
join a on a.parentid = t.rowid
), b as
(
select rowid, parentid,name, 0 level from #t where parentid is null
union all
select t.rowid, t.parentid,t.name, level + 1
from b join #t t on b.rowid = t.parentid
)
select rowid, parentid, name from b
where level = (select max(level)-1 from a)
rowid parentid name
5 2 Leaf1
3 1 Leaf1
4 1 Leaf2