I have a table [Departments] with 2 columns:
[IdDepartment]
[IdSubDepartment]
The table is a kind of hierarchy:
IdDepartment | IdSubDepartment
1 | 2
1 | 3
2 | 4
3 | 5
If I search for department 5 I want to get the following 5 -> 3 -> 1
(I only need the X level every time - not always the root).
I have written a query that gets a department ID and returns its 3rd level (say I enter ID 5 and get back 1). It works fast and good. the problem is when i do that for 7K departments, it gets stuck.
I want to convert the table to a pivot like this:
IdDepartment0 | IdDepartment1 | IdDepartment2 ...
1 2 4
1 3 5
important: I know the level of each department.
so, when I get department 5, I know it is on level 2 (IdDepartment2)
so I can query my new table in no time and get each department level I want.
How do I do convert to the new table?
thanks in advance
Eran
This snipped can be expanded to include deeper nesting.
It can propbably be optimized some.
;WITH cteLvl AS
(
SELECT IdDepartment, IdSubDepartment, 0 AS Lvl
FROM Department
WHERE IdDepartment NOT IN (SELECT IdSubDepartment FROM Department WHERE IdSubDepartment IS NOT NULL)
UNION ALL
SELECT B.IdDepartment, B.IdSubDepartment, A.Lvl + 1
FROM cteLvl A
INNER JOIN Department B ON B.IdDepartment = A.IdSubDepartment
)
, cteLeaf AS
(
SELECT *, ROW_NUMBER() OVER(ORDER BY IdDepartment) AS GroupId
FROM Department
WHERE IdSubDepartment IS NULL
UNION ALL
SELECT B.IdDepartment, B.IdSubDepartment, A.GroupId
FROM cteLeaf A
INNER JOIN Department B ON A.IdDepartment = B.IdSubDepartment
)
, cteCombined AS
(
SELECT A.IdDepartment, A.GroupId, B.Lvl FROM cteLeaf A
INNER JOIN (SELECT DISTINCT IdDepartment, Lvl FROM cteLvl) B ON A.IdDepartment = B.IdDepartment
)
--SELECT * FROM cteCombined
SELECT GroupId, [0] AS Dep0, [1] AS Dep1, [2] AS Dep2, [3] AS Dep3, [4] AS Dep4
FROM
(SELECT GroupId, Lvl, IdDepartment
FROM cteCombined) P
PIVOT
(
SUM(IdDepartment)
FOR Lvl IN
( [0], [1], [2], [3], [4] )
) AS V
Same effect without using the PIVOT construct:
SELECT
GroupId,
MAX(CASE Lvl WHEN 0 THEN IdDepartment END) AS Dep0,
MAX(CASE Lvl WHEN 1 THEN IdDepartment END) AS Dep1,
MAX(CASE Lvl WHEN 2 THEN IdDepartment END) AS Dep2,
MAX(CASE Lvl WHEN 3 THEN IdDepartment END) AS Dep3
FROM cteCombined
GROUP BY GroupId
Related
I have a table Contacts that basically looks like following:
Id | Name | ContactId | Contact | Amount
---------------------------------------------
1 | A | 1 | 12323432 | 555
---------------------------------------------
1 | A | 2 | 23432434 | 349
---------------------------------------------
2 | B | 3 | 98867665 | 297
--------------------------------------------
2 | B | 4 | 88867662 | 142
--------------------------------------------
2 | B | 5 | null | 698
--------------------------------------------
Here, ContactId is unique throughout the table. Contact can be NULL & I would like to exclude those.
Now, I want to select top 5 contacts for each Id based on their Amount. I am accomplished that by following query:
WITH cte AS (
SELECT id, Contact, amount, ROW_NUMBER()
over (
PARTITION BY id
order by amount desc
) AS RowNo
FROM contacts
where contact is not null
)
select *from cte where RowNo <= 5
It's working fine upto this point. Now I want to concate these (<=5) record for each group & show them in a single row by concatenating them.
Expected Result :
Id | Name | Contact
-------------------------------
1 | A | 12323432;23432434
-------------------------------
2 | B | 98867665;88867662
I am using following query to achieve this but it still gives all records in separate rows and also including Null values too:
WITH cte AS (
SELECT id, Contact, amount,contactid, ROW_NUMBER()
over (
PARTITION BY id
order by amount desc
) AS RowNo
FROM contacts
where contact is not null
)
select *from id, name,
STUFF ((
SELECT distinct '; ' + isnull(contact,'') FROM cte
WHERE co.id= cte.id and co.contactid= cte.contactid
and RowNo <= 5
FOR XML PATH('')),1, 1, '')as contact
from contacts co inner join cte where cte.id = co.id and co.contactid= cte.contactid
Above query still gives me all top 5 contacts in diff rows & including null too.
Is it a good idea to use CTE and STUFF togather? Please suggest if there is any better approach than this.
I got the problem with my final query:
I don't need original Contact table in my final Select, since I already have everything I needed in CTE. Also, Inside STUFF(), I'm using contactid to join which is what actually I'm trying to concat here. Since I'm using that condition for join, I am getting records in diff rows. I've removed these 2 condition and it worked.
WITH cte AS (
SELECT id, Contact, amount,contactid, ROW_NUMBER()
over (
PARTITION BY id
order by amount desc
) AS RowNo
FROM contacts
where contact is not null
)
select *from id, name,
STUFF ((
SELECT distinct '; ' + isnull(contact,'') FROM cte
WHERE co.id= cte.id
and RowNo <= 5
FOR XML PATH('')),1, 1, '')as contact
from cte where rowno <= 5
You can use conditional aggregation:
id, name, contact,
select id, name,
concat(max(case when seqnum = 1 then contact + ';' end),
max(case when seqnum = 2 then contact + ';' end),
max(case when seqnum = 3 then contact + ';' end),
max(case when seqnum = 4 then contact + ';' end),
max(case when seqnum = 5 then contact + ';' end)
) as contacts
from (select c.*
row_number() over (partition by id order by amount desc) as seqnum
from contacts c
where contact is not null
) c
group by id, name;
If you are running SQL Server 2017 or higher, you can use string_agg(): as most other aggregate functions, it ignores null values by design.
select id, name, string_agg(contact, ',') within group (order by rn) all_contacts
from (
select id, name, contact
row_number() over (partition by id order by amount desc) as rn
from contacts
where contact is not null
) t
where rn <= 5
group by id, name
Note that you don't strictly need a CTE here; you can return the columns you need from the subquery, and use them directly in the outer query.
In earlier versions, one approach using stuff() and for xml path is:
with cte as (
select id, name, contact,
row_number() over (partition by id order by amount desc) as rn
from contacts
where contact is not null
)
select id, name,
stuff(
(
select ', ' + c1.concat
from cte c1
where c1.id = c.id and c1.rn <= 5
order by c1.rn
for xml path (''), type
).value('.', 'varchar(max)'), 1, 2, ''
) all_contacts
from cte
group by id, name
I agree with #GMB. STRING_AGG() is what you need ...
WITH
contacts(Id,nm,ContactId,Contact,Amount) AS (
SELECT 1,'A',1,12323432,555
UNION ALL SELECT 1,'A',2,23432434,349
UNION ALL SELECT 2,'B',3,98867665,297
UNION ALL SELECT 2,'B',4,88867662,142
UNION ALL SELECT 2,'B',5,NULL ,698
)
,
with_filter_val AS (
SELECT
*
, ROW_NUMBER() OVER(PARTITION BY id ORDER BY amount DESC) AS rn
FROM contacts
)
SELECT
id
, nm
, STRING_AGG(CAST(contact AS CHAR(8)),',') AS contact_list
FROM with_filter_val
WHERE rn <=5
GROUP BY
id
, nm
-- out id | nm | contact_list
-- out ----+----+-------------------
-- out 1 | A | 12323432,23432434
-- out 2 | B | 98867665,88867662
I have parent child relation SQL table
LOCATIONDETAIL Table
OID NAME PARENTOID
1 HeadSite 0
2 Subsite1 1
3 subsite2 1
4 subsubsite1 2
5 subsubsite2 2
6 subsubsite3 3
RULESETCONFIG
OID LOCATIONDETAILOID VALUE
1 1 30
2 4 15
If i provide Input as LOCATIONDETAIL 6, i should get RULESETCONFIG value as 30
because for
LOCATIONDETAIL 6, parentid is 3 and for LOCATIONDETAIL 3 there is no value in RULESETCONFIG,
LOCATIONDETAIL 3 has parent 1 which has value in RULESETCONFIG
if i provide Input as LOCATIONDETAIL 4, i should get RULESETCONFIG value 15
i have code to populate the tree, but don't know how to find the next available Parent
;WITH GLOBALHIERARCHY AS
(
SELECT A.OID,A.PARENTOID,A.NAME
FROM LOCATIONDETAIL A
WHERE OID = #LOCATIONDETAILOID
UNION ALL
SELECT A.OID,A.PARENTOID,A.NAME
FROM LOCATIONDETAIL A INNER JOIN GLOBALHIERARCHY GH ON A.PARENTOID = GH.OID
)
SELECT * FROM GLOBALHIERARCHY
This will return the next parent with a value. If you want to see all, remove the top 1 from the final select.
dbFiddle
Example
Declare #Fetch int = 4
;with cteHB as (
Select OID
,PARENTOID
,Lvl=1
,NAME
From LOCATIONDETAIL
Where OID=#Fetch
Union All
Select R.OID
,R.PARENTOID
,P.Lvl+1
,R.NAME
From LOCATIONDETAIL R
Join cteHB P on P.PARENTOID = R.OID)
Select Top 1
Lvl = Row_Number() over (Order By A.Lvl Desc )
,A.OID
,A.PARENTOID
,A.NAME
,B.Value
From cteHB A
Left Join RULESETCONFIG B on A.OID=B.OID
Where B.VALUE is not null
and A.OID <> #Fetch
Order By 1 Desc
Returns when #Fetch=4
Lvl OID PARENTOID NAME Value
2 2 1 Subsite1 15
Returns when #Fetch=6
Lvl OID PARENTOID NAME Value
1 1 0 HeadSite 30
This should do the job:
;with LV as (
select OID ID,PARENTOID PID,NAME NAM, VALUE VAL FROM LOCATIONDETAIL
left join RULESETCONFIG ON LOCATIONDETAILOID=OID
), GH as (
select ID gID,PID gPID,NAM gNAM,VAL gVAL from LV where ID=#OID
union all
select ID,PID,NAM,VAL FROM LV INNER JOIN GH ON gVAL is NULL AND gPID=ID
)
select * from GH WHERE gVAL>0
See here for e little demo: http://rextester.com/OXD40496
My table
id name num
1 a 3
2 b 4
I need to return every row num number of times. I do it this way.
select DB.BAN_KEY as BAN_KEY, DB.CUST_FULLNAME as CUST_FULLNAME
from TST_DIM_BAN_SELECTED DB
inner join (select rownum rn from dual connect by level < 10) a
on a.rn <= DB.N
There resulting table looks like this.
id name
1 a
1 a
1 a
2 b
2 b
2 b
2 b
But I also need every row in the group to be numbered like this.
id name row_num
1 a 1
1 a 2
1 a 3
2 b 1
2 b 2
2 b 3
2 b 4
How can I do it?
You don't need an inner join to a dummy table or an analytic function to generate the row numbers; you could just use connect by (and its corresponding level function) on the table itself, like so:
WITH tst_dim_ban_selected AS (SELECT 1 ban_key, 'a' cust_fullname, 3 n FROM dual UNION ALL
SELECT 2 ban_key, 'b' cust_fullname, 4 n FROM dual)
-- end of mimicking your table with data in it. See SQL below
SELECT db.ban_key,
db.cust_fullname,
LEVEL row_num
FROM tst_dim_ban_selected db
CONNECT BY LEVEL <= db.n
AND PRIOR db.ban_key = db.ban_key -- assuming this is the primary key
AND PRIOR sys_guid() IS NOT NULL;
BAN_KEY CUST_FULLNAME ROW_NUM
---------- ------------- ----------
1 a 1
1 a 2
1 a 3
2 b 1
2 b 2
2 b 3
2 b 4
If you have other columns than ban_key in the table's primary key, you need to make sure they are included in the connect by clause's list of prior <column> = <column>s. This is so the connect by can identify each row uniquely, meaning that it's looping just over that row and no others. The PRIOR sys_guid() IS NOT NULL is required to prevent connect by loops from occurring.
You can use analytic function for this:
Select id, name,
row_number() over (partition by id, name order by id, name)
From(/* your query */) t;
This can be done without subquery:
Select id, name,
row_number() over (partition by id, name order by id, name)
From /* joins */
You could use this:
SELECT db.ban_key AS ban_key, db.cust_fullname AS cust_fullname,
ROW_NUMBER() OVER (PARTITION BY db.n ORDER BY db.ban_key) AS row_num
FROM tst_dim_ban_selected db
INNER JOIN (SELECT rownum rn FROM dual CONNECT BY level < 10) a
ON a.rn <= db.n;
Use a recursive sub-query factoring clause:
WITH split ( id, name, rn, n ) AS (
SELECT BAN_KEY, CUST_FULLNAME, 1, N
FROM TST_DIM_BAN_SELECTED
UNION ALL
SELECT id, name, rn + 1, n
FROM split
WHERE rn < n
)
SELECT id, name, rn
FROM split;
Let's say I have a simple table of documents with a type column:
Documents
Id Type
1 A
2 A
3 B
4 C
5 C
6 A
7 A
8 A
9 B
10 C
Users have permissions to access different types of documents:
Permissions
Type User
A John
A Jane
B Sarah
C Peter
C John
C Mark
And I need to distribute those documents among the users as tasks:
Tasks
Id T DocId UserId
1 A 1 John
2 A 2 Jane
3 B 3 Sarah
4 C 4 Peter
5 C 5 John
6 A 6 John
7 A 7 Jane
8 A 8 John
9 B 9 Sarah
10 C 10 Mark
How do I do that? How do I get the Tasks?
You can enumerate the rows and then use modulo arithmetic for the matching:
with d as (
select d.*,
row_number() over (partition by type order by newid()) as seqnum,
count(*) over (partition by type) as cnt
from documents d
),
u as (
select u.*,
row_number() over (partition by type order by newid()) as seqnum,
count(*) over (partition by type) as cnt
from users u
)
select d.*
from d join
u
on d.type = u.type and
u.seqnum = (d.seqnum % u.cnt) + 1
Great question.
This solution returns all possible distributions, ordered by priority which is determined by information such as number of user involved, minimum documents per user, standard deviation of tasks per user etc.
I'm not counting on document.id to be a sequence of numbers starting with 1, therfore the use of dense_rank.
The core of the solutions is the iterative CTE which generates the record sets of all possible distributions.
Execution time on my laptop is around 20 seconds, (the iterative part takes 5 seconds)
with doc_user as
(
select d."id" as docid
,p."user" as userid
,dense_rank () over (order by d."id") as doc_seq
from documents d
left join permissions p
on p.type = d.type
)
,it_cte as
(
select docid
,userid
,doc_seq
,cast (coalesce(userid,'') as varchar(max)) as path
,'A' as cte_part
from doc_user
where doc_seq = 1
union all
select r.docid
,r.userid
,du.doc_seq
,r.path + ',' + coalesce (du.userid,'')
,'B'
from it_cte as r
cross join doc_user as du
where du.doc_seq = r.doc_seq + 1
union all
select du.docid
,du.userid
,du.doc_seq
,r.path + ',' + coalesce (du.userid,'')
,'C'
from it_cte as r
cross join doc_user as du
where du.doc_seq = r.doc_seq + 1
and r.cte_part in ('A','C')
)
,result_sets as
(
select dense_rank () over (order by path) as set_id
,docid
,userid
from it_cte
where doc_seq = (select count(*) from documents)
)
,result_sets_stat as
(
select set_id
,count (distinct userid) as users_involved
from result_sets
group by set_id
)
,result_sets_users_stat as
(
select set_id
,min (doc) min_doc_per_user
,stdevp (doc) stdevp_doc_per_user
from (select set_id
,userid
,count (*) as doc
from result_sets
group by set_id
,userid
) t
group by set_id
)
select s.set_priority
,r.docid
,r.userid
,s.users_involved
,s.min_doc_per_user
,s.stdevp_doc_per_user
from (select s.set_id
,s.users_involved
,u.min_doc_per_user
,u.stdevp_doc_per_user
,row_number () over
(
order by s.users_involved desc
,u.min_doc_per_user desc
,u.stdevp_doc_per_user
,s.set_id
) as set_priority
from result_sets_stat as s
join result_sets_users_stat as u
on u.set_id =
s.set_id
) s
join result_sets as r
on r.set_id =
s.set_id
order by s.set_priority
,r.docid
option (merge join)
;
My table structure is below :
MyTable (ID Int, AccID1 Int, AccID2 Int, AccID3 int)
ID AccID1 AccID2 AccID3
---- -------- -------- --------
1 12 2 NULL
2 4 12 1
3 NULL NULL 5
4 7 NULL 1
I want to create indexed view with below output :
ID Level Value
---- ----- -------
1 1 12
1 2 2
2 1 4
2 2 12
2 3 1
3 3 5
4 1 7
4 3 1
EDIT :
My table is very huge and I want to have above output.
I can Get my query such as below :
Select ID,
Case StrLevel
When 'AccID1' Then 1
When 'AccID2' Then 2
Else 3
End AS [Level],
AccID as Value
From (
Select A.ID, A.AccID1, A.AccID2, A.AccID3
From MyTable A
)as p
UNPIVOT (AccID FOR [StrLevel] IN (AccID1, AccID2, AccID3)) AS unpvt
or
Select *
from (
select MyTable.ID,
num.n as [Level],
Case Num.n
When 1 Then MyTable.AccID1
When 2 Then MyTable.AccID2
Else MyTable.AccID3
End AS AccID
from myTable
cross join (select 1
union select 2
union select 3)Num(n)
)Z
Where Z.AccID IS NOT NULL
or
Select A.ID,
2 AS [Level],
A.AccID1 AS AccID
From MyTable A
Where A.AccID1 IS NOT NULL
Union
Select A.ID,
2 AS [Level],
A.AccID2
From MyTable A
Where A.AccID2 IS NOT NULL
Union
Select A.ID,
3 AS [Level],
A.AccID3
From MyTable A
Where A.AccID3 IS NOT NULL
But Above query is slow and I want to have indexed view to have better performance.
and in indexed view I can't use UNION or UNPIVOT or CROSS JOIN in indexed view.
What if you created a Numbers table to essentially do the work of your illegal CROSS JOIN?
Create Table Numbers (number INT NOT NULL PRIMARY KEY)
Go
Insert Numbers
Select top 30000 row_number() over (order by (select 1)) as rn
from sys.all_objects s1 cross join sys.all_objects s2
go
Create view v_unpivot with schemabinding
as
Select MyTable.ID,
n.number as [Level],
Case n.number
When 1 Then MyTable.AccID1
When 2 Then MyTable.AccID2
Else MyTable.AccID3
End AS AccID
From dbo.Mytable
Join dbo.Numbers n on n.number BETWEEN 1 AND 3
go
Create unique clustered index pk_v_unpivot on v_unpivot (ID, [Level])
go
Select
ID,
[Level],
AccID
From v_unpivot with (noexpand)
Where AccID IS NOT NULL
Order by ID, [Level]
The WHERE AccID IS NOT NULL must be part of the query because derived tables are not allowed in indexed views.