I have this self-referencing table where-in I should get the upline and downline and hierarchy levels without the Parent ID provided.
Any ideas?
Have you tried using recursive CTE?
for example:
assume you have table tbl(EmpId, Name, MngrId) which has self-referencing relationship
create table tbl
(
EmpId int not null,
Name nvarchar(100),
MngrId int null)
insert into tbl(EmpId, Name, MngrId)
values (1,'Adel',Null),
(2,'Ali',1),
(3,'Shaban',1),
(4,'Mark',3),
(5,'John',3),
(6,'Tony',Null),
(7,'Peter',6)
You can create some view like that:
create view Employees
Begin
with cte
as
(
Select EmpId,Name, Null as MngrId, cast(null as nvarchar(100)) as MngrName, 1 as EmpLevel
from tbl
where MngrId is Null
Union All
Select t.EmpId, t.Name, c.EmpId as MngrId, c.Name as MngrName, c.EmpLevel + 1 as EmpLevel
from tbl t
inner join cte c
on t.MngrId = c.EmpId
)
Select *
from cte
order by EmpLevel, EmpId
End
You can now use EmpLevel to jump between different levels and MngrName to get information about parent node
Related
Helle there
I'd like to get a hierarchical data parent / childs. meaning that if i select tje id of the parent, all its chilren will be in the record
Their relations are defined by the parent UUID
I have in a DB the following data :
INSERT INTO dummy_table (Id, parent) VALUES ('0171a28a-578a-49b5-86d5-ff0df54c8e96', '0171a28a-578a-49b5-86d5-ff0df54c8e96')
INSERT INTO dummy_table (Id, parent) VALUES ('0171a28a-5809-4708-9fc9-aeb91c16e560', '0171a28a-578a-49b5-86d5-ff0df54c8e96')
INSERT INTO dummy_table (Id, parent) VALUES ('0171a28a-580b-4de9-b3fa-35f13df27dd5', '0171a28a-5809-4708-9fc9-aeb91c16e560')
INSERT INTO dummy_table (Id, parent) VALUES ('0171a28a-580c-4e6b-8d17-0cc18af24b25', '0171a28a-580b-4de9-b3fa-35f13df27dd5')
INSERT INTO dummy_table (Id, parent) VALUES ('0171a28a-580d-47ee-aa15-92c6727e657e', '0171a28a-580c-4e6b-8d17-0cc18af24b25')
And my request is the following :
WITH RECURSIVE cte AS (
SELECT id, parent FROM dummy_table WHERE id = '0171a28a-578a-49b5-86d5-ff0df54c8e96'
UNION ALL
SELECT dt.id, dt.parent FROM dummy_table dt INNER JOIN cte ON cte.parent = dt.id
)
SELECT * FROM cte;
The problem i have is that it loops and I cannot figure out why.
Any help please ?
Thanks you all
That query goes into a loop because the first row in your data references itself as its parent and so the recursion never stops. Add a check to avoid self-reference and you should be fine
WITH RECURSIVE cte AS (
SELECT id, parent FROM dummy_table WHERE id = '0171a28a-578a-49b5-86d5-ff0df54c8e96'
UNION ALL
SELECT dt.id, dt.parent FROM dummy_table dt INNER JOIN cte ON cte.parent = dt.id and cte.id <> dt.id
)
SELECT * FROM cte;
Another option is setting parent as null in the rows where parent is equal to id
I have a simple data set that looks like this:
Name Code
A A-One
A A-Two
B B-One
C C-One
C C-Two
C C-Three
I want to output it so it looks like this:
Name Code1 Code2 Code3 Code4 Code...n ...
A A-One A-Two
B B-One
C C-One C-Two C-Three
For each of the 'Name' values, there can be an undetermined number of 'Code' values.
I have been looking at various examples of Pivot SQL [including simple Pivot sql and sql using the XML function?] but I have not been able to figure this out - or to understand if it is even possible.
I would appreciate any help or pointers.
Thanks!
Try it like this:
DECLARE #tbl TABLE([Name] VARCHAR(100),Code VARCHAR(100));
INSERT INTO #tbl VALUES
('A','A-One')
,('A','A-Two')
,('B','B-One')
,('C','C-One')
,('C','C-Two')
,('C','C-Three');
SELECT p.*
FROM
(
SELECT *
,CONCAT('Code',ROW_NUMBER() OVER(PARTITION BY [Name] ORDER BY Code)) AS ColumnName
FROM #tbl
)t
PIVOT
(
MAX(Code) FOR ColumnName IN (Code1,Code2,Code3,Code4,Code5 /*add as many as you need*/)
)p;
This line
,CONCAT('Code',ROW_NUMBER() OVER(PARTITION BY [Name] ORDER BY Code)) AS ColumnName
will use a partitioned ROW_NUMBER in order to create numbered column names per code. The rest is simple PIVOT...
UPDATE: A dynamic approach to reflect the max amount of codes per group
CREATE TABLE TblTest([Name] VARCHAR(100),Code VARCHAR(100));
INSERT INTO TblTest VALUES
('A','A-One')
,('A','A-Two')
,('B','B-One')
,('C','C-One')
,('C','C-Two')
,('C','C-Three');
DECLARE #cols VARCHAR(MAX);
WITH GetMaxCount(mc) AS(SELECT TOP 1 COUNT([Code]) FROM TblTest GROUP BY [Name] ORDER BY COUNT([Code]) DESC)
SELECT #cols=STUFF(
(
SELECT CONCAT(',Code',Nmbr)
FROM
(SELECT TOP((SELECT mc FROM GetMaxCount)) ROW_NUMBER() OVER(ORDER BY (SELECT NULL)) FROM master..spt_values) t(Nmbr)
FOR XML PATH('')
),1,1,'');
DECLARE #sql VARCHAR(MAX)=
'SELECT p.*
FROM
(
SELECT *
,CONCAT(''Code'',ROW_NUMBER() OVER(PARTITION BY [Name] ORDER BY Code)) AS ColumnName
FROM TblTest
)t
PIVOT
(
MAX(Code) FOR ColumnName IN (' + #cols + ')
)p;';
EXEC(#sql);
GO
DROP TABLE TblTest;
As you can see, the only part which will change in order to reflect the actual amount of columns is the list in PIVOTs IN() clause.
You can create a string, which looks like Code1,Code2,Code3,...CodeN and build the statement dynamically. This can be triggered with EXEC().
I'd prefer the first approach. Dynamically created SQL is very mighty, but can be a pain in the neck too...
I have a stored procedure with 2 CTEs. The second CTE has a parameter
WITH path_sequences
AS
(
),
WITH categories
AS
(
... WHERE CategoryId = #CategoryId
// I dont know how to get this initial parameter inside the CTE
)
SELECT * FROM path_sequences p
JOIN categories c
ON p.CategoryId = c.CategoryId
The initial parameter that I need to get inside the second TCE is p.CategoryId. How do I do that without having to create another stored procedure to contain the second CTE?
Thanks for helping
You can create table valued function
create function ftCategories
(
#CategoryID int
)
returns table
as return
with categories as (
... WHERE CategoryId = #CategoryId
)
select Col1, Col2 ...
from categories
and use it as
SELECT *
FROM path_sequences p
cross apply ftCategories(p.CategoryId) c
I have created simple query using your code. You can use it like -
DECLARE #CategoryId INT
SET #CategoryId = 1
;WITH path_sequences
AS
(
SELECT 1 CategoryId
),
categories
AS
(
SELECT 1 CategoryId WHERE 1 = #CategoryId
)
SELECT * FROM path_sequences p
JOIN categories c
ON p.CategoryId = c.CategoryId
This syntax is for External Aliases:
-- CTES With External Aliases:
WITH Sales_CTE (SalesPersonID, SalesOrderID, SalesYear)
AS
-- Define the CTE query.
(
SELECT SalesPersonID, SalesOrderID, YEAR(OrderDate) AS SalesYear
FROM Sales.SalesOrderHeader
WHERE SalesPersonID IS NOT NULL
)
The only way to add parameters is to use scope variables like so:
--Declare a variable:
DECLARE #category INT
WITH
MyCTE1 (exName1, exName2)
AS
(
SELECT <SELECT LIST>
FROM <TABLE LIST>
--Use the variable as 'a parameter'
WHERE CategoryId = #CategoryId
)
First remove the second WITH, separate each cte with just a comma. Next you can add parameters like this:
DECLARE #category INT; -- <~~ Parameter outside of CTEs
WITH
MyCTE1 (col1, col2) -- <~~ were poorly named param1 and param2 previously
AS
(
SELECT blah blah
FROM blah
WHERE CategoryId = #CategoryId
),
MyCTE2 (col1, col2) -- <~~ were poorly named param1 and param2 previously
AS
(
)
SELECT *
FROM MyCTE2
INNER JOIN MyCTE1 ON ...etc....
EDIT (and CLARIFICATION):
I have renamed the columns from param1 and param2 to col1 and col2 (which is what I meant originally).
My example assumes that each SELECT has exactly two columns. The columns are optional if you want to return all of the columns from the underlying query AND those names are unique. If you have more or less columns than what is being SELECTed you will need to specify names.
Here is another example:
Table:
CREATE TABLE Employee
(
Id INT NOT NULL IDENTITY PRIMARY KEY CLUSTERED,
FirstName VARCHAR(50) NOT NULL,
LastName VARCHAR(50) NOT NULL,
ManagerId INT NULL
)
Fill table with some rows:
INSERT INTO Employee
(FirstName, LastName, ManagerId)
VALUES
('Donald', 'Duck', 5)
INSERT INTO Employee
(FirstName, LastName, ManagerId)
VALUES
('Micky', 'Mouse', 5)
INSERT INTO Employee
(FirstName, LastName, ManagerId)
VALUES
('Daisy', 'Duck', 5)
INSERT INTO Employee
(FirstName, LastName, ManagerId)
VALUES
('Fred', 'Flintstone', 5)
INSERT INTO Employee
(FirstName, LastName, ManagerId)
VALUES
('Darth', 'Vader', null)
INSERT INTO Employee
(FirstName, LastName, ManagerId)
VALUES
('Bugs', 'Bunny', null)
INSERT INTO Employee
(FirstName, LastName, ManagerId)
VALUES
('Daffy', 'Duck', null)
CTEs:
DECLARE #ManagerId INT = 5;
WITH
MyCTE1 (col1, col2, col3, col4)
AS
(
SELECT *
FROM Employee e
WHERE 1=1
AND e.Id = #ManagerId
),
MyCTE2 (colx, coly, colz, cola)
AS
(
SELECT e.*
FROM Employee e
INNER JOIN MyCTE1 mgr ON mgr.col1 = e.ManagerId
WHERE 1=1
)
SELECT
empsWithMgrs.colx,
empsWithMgrs.coly,
empsWithMgrs.colz,
empsWithMgrs.cola
FROM MyCTE2 empsWithMgrs
Notice in the CTEs the columns are being aliased. MyCTE1 exposes columns as col1, col2, col3, col4 and MyCTE2 references MyCTE1.col1 when it references it. Notice the final select uses MyCTE2's column names.
Results:
For anyone still struggling with this, the only thing you need to is terminate your declaration of variables with a semicolon before the CTE. Nothing else is required.
DECLARE #test AS INT = 42;
WITH x
AS (SELECT #test AS 'Column')
SELECT *
FROM x
Results:
Column
-----------
42
(1 row affected)
I need to copy content from one table to itself and related tables... Let me schematize the problem. Let's say I have two tables:
Order
OrderID : int
CustomerID : int
OrderName : nvarchar(32)
OrderItem
OrderItemID : int
OrderID : int
Quantity : int
With the PK being autoincremental.
Let's say I want to duplicate the content of one customer to another. How do I do that efficiently?
The problem are the PKs. I would need to map the values of OrderIDs from the original set of data to the copy in order to create proper references in OrderItem. If I just select-Insert, I won't be able to create that map.
Suggestions?
For duplicating one parent and many children with identities as the keys, I think the OUTPUT clause can make things pretty clean (SqlFiddle here):
-- Make a duplicate of parent 1, including children
-- Setup some test data
create table Parents (
ID int not null primary key identity
, Col1 varchar(10) not null
, Col2 varchar(10) not null
)
insert into Parents (Col1, Col2) select 'A', 'B'
insert into Parents (Col1, Col2) select 'C', 'D'
insert into Parents (Col1, Col2) select 'E', 'F'
create table Children (
ID int not null primary key identity
, ParentID int not null references Parents (ID)
, Col1 varchar(10) not null
, Col2 varchar(10) not null
)
insert into Children (ParentID, Col1, Col2) select 1, 'g', 'h'
insert into Children (ParentID, Col1, Col2) select 1, 'i', 'j'
insert into Children (ParentID, Col1, Col2) select 2, 'k', 'l'
insert into Children (ParentID, Col1, Col2) select 3, 'm', 'n'
-- Get one parent to copy
declare #oldID int = 1
-- Create a place to store new ParentID
declare #newID table (
ID int not null primary key
)
-- Create new parent
insert into Parents (Col1, Col2)
output inserted.ID into #newID -- Capturing the new ParentID
select Col1, Col2
from Parents
where ID = #oldID -- Only one parent
-- Create new children using the new ParentID
insert into Children (ParentID, Col1, Col2)
select n.ID, c.Col1, c.Col2
from Children c
cross join #newID n
where c.ParentID = #oldID -- Only one parent
-- Show some output
select * from Parents
select * from Children
Do you have to have the primary keys from table A as primaries in Table B? If not you can do a select statement with an insert into. Primary Key's are usually int's that start from an ever increasing seed (identity). Going around this and declaring an insert of this same data problematically has the disadvantage of someone thinking this is a distinct key set on this table and not a 'relationship' or foreign key value.
You can Select Primary Key's for inserts into other tables, just not themselves.... UNLESS you set the 'identity insert on' hint. Do not do this unless you know what this does as you can create more problems than it's worth if you don't understand the ramifications.
I would just do the ole:
insert into TableB
select *
from TableA
where (criteria)
Simple example (This assumes SQL Server 2008 or higher). My bad I did not see you did not list TSQL framework. Not sure if this will run on Oracle or MySql.
declare #Order Table ( OrderID int identity primary key, person varchar(8));
insert into #Order values ('Brett'),('John'),('Peter');
declare #OrderItem Table (orderItemID int identity primary key, OrderID int, OrderInfo varchar(16));
insert into #OrderItem
select
OrderID -- I can insert a primary key just fine
, person + 'Stuff'
from #Order
select *
from #Order
Select *
from #OrderItem
Add an extra helper column to Order called OldOrderID
Copy all the Order's from the #OldCustomerID to the #NewCustomerID
Copy all of the OrderItems using the OldOrderID column to help make the relation
Remove the extra helper column from Order
ALTER TABLE Order ADD OldOrderID INT NULL
INSERT INTO Order (CustomerID, OrderName, OldOrderID)
SELECT #NewCustomerID, OrderName, OrderID
FROM Order
WHERE CustomerID = #OldCustomerID
INSERT INTO OrderItem (OrderID, Quantity)
SELECT o.OrderID, i.Quantity
FROM Order o INNER JOIN OrderItem i ON o.OldOrderID = i.OrderID
WHERE o.CustomerID = #NewCustomerID
UPDATE Order SET OldOrderID = null WHERE OldOrderID IS NOT NULL
ALTER TABLE Order DROP COLUMN OldOrderID
IF the OrderName is unique per customer, you could simply do:
INSERT INTO [Order] ([CustomerID], [OrderName])
SELECT
2 AS [CustomerID],
[OrderName]
FROM [Order]
WHERE [CustomerID] = 1
INSERT INTO [OrderItem] ([OrderID], [Quantity])
SELECT
[o2].[OrderID],
[oi1].[Quantity]
FROM [OrderItem] [oi1]
INNER JOIN [Order] [o1] ON [oi1].[OrderID] = [o1].[OrderID]
INNER JOIN [Order] [o2] ON [o1].[OrderName] = [o2].[OrderName]
WHERE [o1].[CustomerID] = 1 AND [o2].[CustomerID] = 2
Otherwise, you will have to use a temporary table or alter the existing Order table like #LastCoder suggested.
I need to be able to return a list of all children given a parent Id at all levels using SQL.
The table looks something like this:
ID ParentId Name
---------------------------------------
1 null Root
2 1 Child of Root
3 2 Child of Child of Root
Give an Id of '1', how would I return the entire list...? There is no limitation on the depth of the nesting either...
Thanks,
Kieron
To get all children for a given #ParentId stored in that manner you could use a recursive CTE.
declare #ParentId int
--set #ParentId = 1
;WITH T AS
(
select 1 AS ID,null AS ParentId, 'Root' as [Name] union all
select 2,1,'Child of Root' union all
select 3,2,'Child of Child of Root'
),
cte AS
(
SELECT ID, ParentId, Name
FROM T
WHERE ParentId = #ParentId OR (ParentId IS NULL AND #ParentId IS NULL)
UNION ALL
SELECT T.ID, T.ParentId, T.Name
FROM T
JOIN cte c ON c.ID = T.ParentId
)
SELECT ID, ParentId, Name
FROM cte
OPTION (MAXRECURSION 0)