I'm sure this has been asked somewhere, but I found it difficult to search for.
If I want to get all records where a column value equals one in a list, I'd use the IN operator.
SELECT idSparePart, SparePartName
FROM tabSparePart
WHERE SparePartName IN (
'1234-2043','1237-8026','1238-1036','1238-1039','1223-5172'
)
Suppose this SELECT returns 4 rows although the list has 5 items. How can I select the value that does not occur in the table?
Thanks in advance.
select t.* from (
select '1234-2043' as sparePartName
union select '1237-8026'
union select '1238-1036'
union select '1238-1039'
union select '1223-5172'
) t
where not exists (
select 1 from tabSparePart p WHERE p.SparePartName = t.sparePartName
)
As soon as you mentioned that i have to create a temp table, i remembered my Split-function.
Sorry for answering my own question, but this might be the the best/simplest way for me:
SELECT PartNames.Item
FROM dbo.Split('1234-2043,1237-8026,1238-1036,1238-1039,1223-5172', ',') AS PartNames
LEFT JOIN tabSparePart ON tabSparePart.SparePartName = PartNames.Item
WHERE idSparePart IS NULL
My Split-function:
Help with a sql search query using a comma delimitted parameter
Thank you all anyway.
Update: I misunderstood the question. I guess in that case I would select the values into a temp table, then select the values which are not in that table. Not ideal, I know -- the problem is that you need to get your list of part names to SQL Server somehow (either via IN or putting them in a temp table) but the semantics of IN don't do what you want.
Something like this:
CREATE TABLE tabSparePart
(
SparePartName nvarchar(50)
)
insert into tabSparePart values('1234-2043')
CREATE TABLE #tempSparePartName
(
SparePartName nvarchar(50)
)
insert into #tempSparePartName values('1234-2043')
insert into #tempSparePartName values('1238-1036')
insert into #tempSparePartName values('1237-8026')
select * from #tempSparePartName
where SparePartName not in (select SparePartName from tabSparePart)
With output:
SparePartName
1238-1036
1237-8026
Original (wrong) answer:
You can just use "not in":
SELECT * from tabSparePart WHERE SparePartName NOT in(
'1234-2043','1237-8026','1238-1036','1238-1039','1223-5172'
)
You could try something like this....
declare #test as table
(
items varchar(50)
)
insert into #test
values('1234-2043')
insert into #test
values('1234-2043')
insert into #test
values('1237-8026')
-- the rest of the values --
select * from #test
where items not in (
select theItemId from SparePartName
)
for fun check this out...
http://blogs.microsoft.co.il/blogs/itai/archive/2009/02/01/t-sql-split-function.aspx
It shows you how to take delimited data and return it from a table valued function as separate "rows"... which my make the process of creating the table to select from easier than inserting into a #table or doing a giant select union subquery.
Related
I need take the id of anexo an then the result id list insert in another table
with new_id as(INSERT INTO
clienteproveedor.anexo
(
codigo,
estado,
facturar,
observaciones,
servicioproductocontratadoid,
formaspagoid
)
select
ServiciosPorAnexo.CodAnexo,
ServiciosPorAnexo.cancelado,
serviciosporanexo.facturacion,
ServiciosPorAnexo.MotivosElim,
ServiciosPorAnexo.codigo_servicio,
ServiciosPorAnexo.FormaPago
from clienteproveedor.serviciosporanexo
returning id);
Yes you can do that, and you are close. Your problem being your returning clause is in the wrong place. Try:
with new_id(id) as
(INSERT INTO
clienteproveedor.anexo
(
codigo,
estado,
facturar,
observaciones,
servicioproductocontratadoid,
formaspagoid
)
retuning id
)
select
ServiciosPorAnexo.CodAnexo,
ServiciosPorAnexo.cancelado,
serviciosporanexo.facturacion,
ServiciosPorAnexo.MotivosElim,
ServiciosPorAnexo.codigo_servicio,
ServiciosPorAnexo.FormaPago
from clienteproveedor.serviciosporanexo
where ServiciosPorAnexo.id in
(select id from new_id);
NOTE: Not tested as I do not have table definitions nor example data.
I have a union of 3 queries that summarizes like this...
Select param1 As 'example1' And .... Where...
Union All
Select param1 As 'example2' And .... Where...
Union All
Select param1 As 'example3' And .... Where...
Is there any way to wrap this in a Select and create an optional parameter that filters on example1/example2/example3?
Any help would be greatly appreciated. Thanks!
Sorry everyone...when I was brainstorming in my head, I had my query wrong and I'm not very good at sql anyway. But what I want to do was filter on the created column of AccountStatus as an optional parameter. Is there some way to capture all this and then add an optional parameter to filter on the created column?
Select 'Red Account' As AccountStatus And .... Where OverdueDays >= 30
Union All
Select 'Yellow Account' As AccountStatus And .... Where 10 < OverdueDays < 30
Union All
Select 'Green Account' As AccountStatus And .... Where OverdueDays <= 10
Is there any way to wrap this in a Select and create an optional parameter that filters on example1/example2/example3?
Assuming that I understood your need then you can use common table expression (CTE).
In the following document you can read more about the option of using CTE:
https://learn.microsoft.com/en-us/sql/t-sql/queries/with-common-table-expression-transact-sql?view=sql-server-ver15
In general, you wrap your code into a CTE (in the following example I will name my CTE MyCTE but you can use any name), and then in the outside query you can add the filter which you want.
Do not confuse between CTE and a variable or temporary table. A CTE is not a physical entity but logically for the sake pf the query and the server will parse it as inline code.
For example:
;With MyCTE as ( <here comes the code you want to wrap> )
SELECT <choose columns to select>
FROM MyCTE
<here you can add order by or filetring with where>
In your case it might look like:
;With MyCTE as (
-- when you use UNION then the name of the columns in the result is configured by the names in the first query, so you do not need all the "as..." for the other queries.
-- not clear why you use "And" in the name of the columns you select. If you need more than one column then you should use comma "," between the columns
Select param1 As [example1], column2, column3... Where... <this filter only this specific query>
Union All
Select param1, column2, column3.... Where...
Union All
Select param1, column2, column3.... Where...
)
SELECT param1, column2, column3....
FROM MyCTE -- we select from the logical CTE as it was a table
WHERE <here you can add condition to filter the result of the UNION>
Yes it is possible. And here is where you should make the effort provide consumable information that you and everyone else can use as a basis for a solution. Below is the code in this fiddle which you can play with.
-- "parameters"
--declare #p1 varchar(20) = null;
declare #p1 varchar(20) = 'waggle';
-- some crap data
declare #x table (id int, trandate date);
insert #x (id, trandate) values
(1, '20190101'), (2, '20190425'),
(4, '20200311'), (5, '20200630'), (11, '20200801'),
(12, '20210101'), (13, '20210710');
with crap_union as (
select 'wiggle' as [when], id, trandate
from #x where year(trandate) = 2019
union all
select 'waggle' as [when], id, trandate
from #x where year(trandate) = 2020
union all
select 'waddle' as [when], id, trandate
from #x where year(trandate) = 2021
)
select * from crap_union
where [when] = #p1 or #p1 is null
order by [when], id, trandate
;
Same idea as generically expressed by Ronen. You add some sort of identifier to each query in the UNION. That allows you to "see" which row comes from which query. You stuff that UNION into a CTE or a derived table (same logical effect) and then select from that CTE (or derived table) with the desired filter.
You might consider reading Erland's discussion on dynamic search conditions to understand the performance considerations of this approach. Bookmark Erland's website since it has much useful information.
I'm attempting to do an essentially very simple task, which is resulting in:
ORA-00928: missing SELECT keyword
All I'm trying to do is persist the results from periods into table globalTable. Selecting works fine (I'm returned rows) however as soon as I replace it with the Insert I get the above error.
create global temporary table globalTable
(
ids number(11)
);
with periods as
(
select cl.id uniqueId
from inv_mpan_hh_con_lines cl
left join invoice_vat_lines vl on
cl.invoice_id = VL.INVOICE_ID
where rownum < 4
)
--//Issue occurs at insert keyword. If I comment it and uncomment select it works as expected//--
--select uniqueId
insert into globalTable
from periods;
Any pointers are much appreciated.
Try this:
insert into globalTable
with periods as
(
select cl.id uniqueId
from inv_mpan_hh_con_lines cl
left join invoice_vat_lines vl
on cl.invoice_id = VL.INVOICE_ID
where rownum < 4
)
select uniqueId
from periods;
CTE (WITH-clause) is a part of SELECT statement, according to the INSERT syntax you can either specify values or SELECT statement
I need to test my mail server. How can I make a Select statement
that selects say ID=5469 a thousand times.
If I get your meaning then a very simple way is to cross join on a derived query on a table with more than 1000 rows in it and put a top 1000 on that. This would duplicate your results 1000 times.
EDIT: As an example (This is MSSQL, I don't know if Access is much different)
SELECT
MyTable.*
FROM
MyTable
CROSS JOIN
(
SELECT TOP 1000
*
FROM
sysobjects
) [BigTable]
WHERE
MyTable.ID = 1234
You can use the UNION ALL statement.
Try something like:
SELECT * FROM tablename WHERE ID = 5469
UNION ALL
SELECT * FROM tablename WHERE ID = 5469
You'd have to repeat the SELECT statement a bunch of times but you could write a bit of VB code in Access to create a dynamic SQL statement and then execute it. Not pretty but it should work.
Create a helper table for this purpose:
JUST_NUMBER(NUM INT primary key)
Insert (with the help of some (VB) script) numbers from 1 to N. Then execute this unjoined query:
SELECT MYTABLE.*
FROM MYTABLE,
JUST_NUMBER
WHERE MYTABLE.ID = 5469
AND JUST_NUMBER.NUM <= 1000
Here's a way of using a recursive common table expression to generate some empty rows, then to cross join them back onto your desired row:
declare #myData table (val int) ;
insert #myData values (666),(888),(777) --some dummy data
;with cte as
(
select 100 as a
union all
select a-1 from cte where a>0
--generate 100 rows, the max recursion depth
)
,someRows as
(
select top 1000 0 a from cte,cte x1,cte x2
--xjoin the hundred rows a few times
--to generate 1030301 rows, then select top n rows
)
select m.* from #myData m,someRows where m.val=666
substitute #myData for your real table, and alter the final predicate to suit.
easy way...
This exists only one row into the DB
sku = 52 , description = Skullcandy Inkd Green ,price = 50,00
Try to relate another table in which has no constraint key to the main table
Original Query
SELECT Prod_SKU , Prod_Descr , Prod_Price FROM dbo.TB_Prod WHERE Prod_SKU = N'52'
The Functional Query ...adding a not related table called 'dbo.TB_Labels'
SELECT TOP ('times') Prod_SKU , Prod_Descr , Prod_Price FROM dbo.TB_Prod,dbo.TB_Labels WHERE Prod_SKU = N'52'
In postgres there is a nice function called generate_series. So in postgreSQL it is as simple as:
select information from test_table, generate_series(1, 1000) where id = 5469
In this way, the query is executed 1000 times.
Example for postgreSQL:
CREATE EXTENSION IF NOT EXISTS "uuid-ossp"; --To be able to use function uuid_generate_v4()
--Create a test table
create table test_table (
id serial not null,
uid UUID NOT NULL,
CONSTRAINT uid_pk PRIMARY KEY(id));
-- Insert 10000 rows
insert into test_table (uid)
select uuid_generate_v4() from generate_series(1, 10000);
-- Read the data from id=5469 one thousand times
select id, uid, uuid_generate_v4() from test_table, generate_series(1, 1000) where id = 5469;
As you can see in the result below, the data from uid is read 1000 times as confirmed by the generation of a new uuid at every new row.
id |uid |uuid_generate_v4
----------------------------------------------------------------------------------------
5469|"10791df5-ab72-43b6-b0a5-6b128518e5ee"|"5630cd0d-ee47-4d92-9ee3-b373ec04756f"
5469|"10791df5-ab72-43b6-b0a5-6b128518e5ee"|"ed44b9cb-c57f-4a5b-ac9a-55bd57459c02"
5469|"10791df5-ab72-43b6-b0a5-6b128518e5ee"|"3428b3e3-3bb2-4e41-b2ca-baa3243024d9"
5469|"10791df5-ab72-43b6-b0a5-6b128518e5ee"|"7c8faf33-b30c-4bfa-96c8-1313a4f6ce7c"
5469|"10791df5-ab72-43b6-b0a5-6b128518e5ee"|"b589fd8a-fec2-4971-95e1-283a31443d73"
5469|"10791df5-ab72-43b6-b0a5-6b128518e5ee"|"8b9ab121-caa4-4015-83f5-0c2911a58640"
5469|"10791df5-ab72-43b6-b0a5-6b128518e5ee"|"7ef63128-b17c-4188-8056-c99035e16c11"
5469|"10791df5-ab72-43b6-b0a5-6b128518e5ee"|"5bdc7425-e14c-4c85-a25e-d99b27ae8b9f"
5469|"10791df5-ab72-43b6-b0a5-6b128518e5ee"|"9bbd260b-8b83-4fa5-9104-6fc3495f68f3"
5469|"10791df5-ab72-43b6-b0a5-6b128518e5ee"|"c1f759e1-c673-41ef-b009-51fed587353c"
5469|"10791df5-ab72-43b6-b0a5-6b128518e5ee"|"4a70bf2b-ddf5-4c42-9789-5e48e2aec441"
Of course other DBs won't necessarily have the same function but it could be done:
See here.
If your are doing this in sql Server
declare #cnt int
set #cnt = 0
while #cnt < 1000
begin
select '12345'
set #cnt = #cnt + 1
end
select '12345' can be any expression
Repeat rows based on column value of TestTable. First run the Create table and insert statement, then run the following query for the desired result.
This may be another solution:
CREATE TABLE TestTable
(
ID INT IDENTITY(1,1),
Col1 varchar(10),
Repeats INT
)
INSERT INTO TESTTABLE
VALUES ('A',2), ('B',4),('C',1),('D',0)
WITH x AS
(
SELECT TOP (SELECT MAX(Repeats)+1 FROM TestTable) rn = ROW_NUMBER()
OVER (ORDER BY [object_id])
FROM sys.all_columns
ORDER BY [object_id]
)
SELECT * FROM x
CROSS JOIN TestTable AS d
WHERE x.rn <= d.Repeats
ORDER BY Col1;
This trick helped me in my requirement.
here, PRODUCTDETAILS is my Datatable
and orderid is my column.
declare #Req_Rows int = 12
;WITH cte AS
(
SELECT 1 AS Number
UNION ALL
SELECT Number + 1 FROM cte WHERE Number < #Req_Rows
)
SELECT PRODUCTDETAILS.*
FROM cte, PRODUCTDETAILS
WHERE PRODUCTDETAILS.orderid = 3
create table #tmp1 (id int, fld varchar(max))
insert into #tmp1 (id, fld)
values (1,'hello!'),(2,'world'),(3,'nice day!')
select * from #tmp1
go
select * from #tmp1 where id=3
go 1000
drop table #tmp1
in sql server try:
print 'wow'
go 5
output:
Beginning execution loop
wow
wow
wow
wow
wow
Batch execution completed 5 times.
The easy way is to create a table with 1000 rows. Let's call it BigTable. Then you would query for the data you want and join it with the big table, like this:
SELECT MyTable.*
FROM MyTable, BigTable
WHERE MyTable.ID = 5469
I've got a standard boss/subordinate employee table. I need to select a boss (specified by ID) and all his subordinates (and their subrodinates, etc). Unfortunately the real world data has some loops in it (for example, both company owners have each other set as their boss). The simple recursive query with a CTE chokes on this (maximum recursion level of 100 exceeded). Can the employees still be selected? I care not of the order in which they are selected, just that each of them is selected once.
Added: You want my query? Umm... OK... I though it is pretty obvious, but - here it is:
with
UserTbl as -- Selects an employee and his subordinates.
(
select a.[User_ID], a.[Manager_ID] from [User] a WHERE [User_ID] = #UserID
union all
select a.[User_ID], a.[Manager_ID] from [User] a join UserTbl b on (a.[Manager_ID]=b.[User_ID])
)
select * from UserTbl
Added 2: Oh, in case it wasn't clear - this is a production system and I have to do a little upgrade (basically add a sort of report). Thus, I'd prefer not to modify the data if it can be avoided.
I know it has been a while but thought I should share my experience as I tried every single solution and here is a summary of my findings (an maybe this post?):
Adding a column with the current path did work but had a performance hit so not an option for me.
I could not find a way to do it using CTE.
I wrote a recursive SQL function which adds employeeIds to a table. To get around the circular referencing, there is a check to make sure no duplicate IDs are added to the table. The performance was average but was not desirable.
Having done all of that, I came up with the idea of dumping the whole subset of [eligible] employees to code (C#) and filter them there using a recursive method. Then I wrote the filtered list of employees to a datatable and export it to my stored procedure as a temp table. To my disbelief, this proved to be the fastest and most flexible method for both small and relatively large tables (I tried tables of up to 35,000 rows).
this will work for the initial recursive link, but might not work for longer links
DECLARE #Table TABLE(
ID INT,
PARENTID INT
)
INSERT INTO #Table (ID,PARENTID) SELECT 1, 2
INSERT INTO #Table (ID,PARENTID) SELECT 2, 1
INSERT INTO #Table (ID,PARENTID) SELECT 3, 1
INSERT INTO #Table (ID,PARENTID) SELECT 4, 3
INSERT INTO #Table (ID,PARENTID) SELECT 5, 2
SELECT * FROM #Table
DECLARE #ID INT
SELECT #ID = 1
;WITH boss (ID,PARENTID) AS (
SELECT ID,
PARENTID
FROM #Table
WHERE PARENTID = #ID
),
bossChild (ID,PARENTID) AS (
SELECT ID,
PARENTID
FROM boss
UNION ALL
SELECT t.ID,
t.PARENTID
FROM #Table t INNER JOIN
bossChild b ON t.PARENTID = b.ID
WHERE t.ID NOT IN (SELECT PARENTID FROM boss)
)
SELECT *
FROM bossChild
OPTION (MAXRECURSION 0)
what i would recomend is to use a while loop, and only insert links into temp table if the id does not already exist, thus removing endless loops.
Not a generic solution, but might work for your case: in your select query modify this:
select a.[User_ID], a.[Manager_ID] from [User] a join UserTbl b on (a.[Manager_ID]=b.[User_ID])
to become:
select a.[User_ID], a.[Manager_ID] from [User] a join UserTbl b on (a.[Manager_ID]=b.[User_ID])
and a.[User_ID] <> #UserID
You don't have to do it recursively. It can be done in a WHILE loop. I guarantee it will be quicker: well it has been for me every time I've done timings on the two techniques. This sounds inefficient but it isn't since the number of loops is the recursion level. At each iteration you can check for looping and correct where it happens. You can also put a constraint on the temporary table to fire an error if looping occurs, though you seem to prefer something that deals with looping more elegantly. You can also trigger an error when the while loop iterates over a certain number of levels (to catch an undetected loop? - oh boy, it sometimes happens.
The trick is to insert repeatedly into a temporary table (which is primed with the root entries), including a column with the current iteration number, and doing an inner join between the most recent results in the temporary table and the child entries in the original table. Just break out of the loop when ##rowcount=0!
Simple eh?
I know you asked this question a while ago, but here is a solution that may work for detecting infinite recursive loops. I generate a path and I checked in the CTE condition if the USER ID is in the path, and if it is it wont process it again. Hope this helps.
Jose
DECLARE #Table TABLE(
USER_ID INT,
MANAGER_ID INT )
INSERT INTO #Table (USER_ID,MANAGER_ID) SELECT 1, 2
INSERT INTO #Table (USER_ID,MANAGER_ID) SELECT 2, 1
INSERT INTO #Table (USER_ID,MANAGER_ID) SELECT 3, 1
INSERT INTO #Table (USER_ID,MANAGER_ID) SELECT 4, 3
INSERT INTO #Table (USER_ID,MANAGER_ID) SELECT 5, 2
DECLARE #UserID INT
SELECT #UserID = 1
;with
UserTbl as -- Selects an employee and his subordinates.
(
select
'/'+cast( a.USER_ID as varchar(max)) as [path],
a.[User_ID],
a.[Manager_ID]
from #Table a
where [User_ID] = #UserID
union all
select
b.[path] +'/'+ cast( a.USER_ID as varchar(max)) as [path],
a.[User_ID],
a.[Manager_ID]
from #Table a
inner join UserTbl b
on (a.[Manager_ID]=b.[User_ID])
where charindex('/'+cast( a.USER_ID as varchar(max))+'/',[path]) = 0
)
select * from UserTbl
basicaly if you have loops like this in data you'll have to do the retreival logic by yourself.
you could use one cte to get only subordinates and other to get bosses.
another idea is to have a dummy row as a boss to both company owners so they wouldn't be each others bosses which is ridiculous. this is my prefferd option.
I can think of two approaches.
1) Produce more rows than you want, but include a check to make sure it does not recurse too deep. Then remove duplicate User records.
2) Use a string to hold the Users already visited. Like the not in subquery idea that didn't work.
Approach 1:
; with TooMuchHierarchy as (
select "User_ID"
, Manager_ID
, 0 as Depth
from "User"
WHERE "User_ID" = #UserID
union all
select U."User_ID"
, U.Manager_ID
, M.Depth + 1 as Depth
from TooMuchHierarchy M
inner join "User" U
on U.Manager_ID = M."user_id"
where Depth < 100) -- Warning MAGIC NUMBER!!
, AddMaxDepth as (
select "User_ID"
, Manager_id
, Depth
, max(depth) over (partition by "User_ID") as MaxDepth
from TooMuchHierarchy)
select "user_id", Manager_Id
from AddMaxDepth
where Depth = MaxDepth
The line where Depth < 100 is what keeps you from getting the max recursion error. Make this number smaller, and less records will be produced that need to be thrown away. Make it too small and employees won't be returned, so make sure it is at least as large as the depth of the org chart being stored. Bit of a maintence nightmare as the company grows. If it needs to be bigger, then add option (maxrecursion ... number ...) to whole thing to allow more recursion.
Approach 2:
; with Hierarchy as (
select "User_ID"
, Manager_ID
, '#' + cast("user_id" as varchar(max)) + '#' as user_id_list
from "User"
WHERE "User_ID" = #UserID
union all
select U."User_ID"
, U.Manager_ID
, M.user_id_list + '#' + cast(U."user_id" as varchar(max)) + '#' as user_id_list
from Hierarchy M
inner join "User" U
on U.Manager_ID = M."user_id"
where user_id_list not like '%#' + cast(U."User_id" as varchar(max)) + '#%')
select "user_id", Manager_Id
from Hierarchy
The preferrable solution is to clean up the data and to make sure you do not have any loops in the future - that can be accomplished with a trigger or a UDF wrapped in a check constraint.
However, you can use a multi statement UDF as I demonstrated here: Avoiding infinite loops. Part One
You can add a NOT IN() clause in the join to filter out the cycles.
This is the code I used on a project to chase up and down hierarchical relationship trees.
User defined function to capture subordinates:
CREATE FUNCTION fn_UserSubordinates(#User_ID INT)
RETURNS #SubordinateUsers TABLE (User_ID INT, Distance INT) AS BEGIN
IF #User_ID IS NULL
RETURN
INSERT INTO #SubordinateUsers (User_ID, Distance) VALUES ( #User_ID, 0)
DECLARE #Distance INT, #Finished BIT
SELECT #Distance = 1, #Finished = 0
WHILE #Finished = 0
BEGIN
INSERT INTO #SubordinateUsers
SELECT S.User_ID, #Distance
FROM Users AS S
JOIN #SubordinateUsers AS C
ON C.User_ID = S.Manager_ID
LEFT JOIN #SubordinateUsers AS C2
ON C2.User_ID = S.User_ID
WHERE C2.User_ID IS NULL
IF ##RowCount = 0
SET #Finished = 1
SET #Distance = #Distance + 1
END
RETURN
END
User defined function to capture managers:
CREATE FUNCTION fn_UserManagers(#User_ID INT)
RETURNS #User TABLE (User_ID INT, Distance INT) AS BEGIN
IF #User_ID IS NULL
RETURN
DECLARE #Manager_ID INT
SELECT #Manager_ID = Manager_ID
FROM UserClasses WITH (NOLOCK)
WHERE User_ID = #User_ID
INSERT INTO #UserClasses (User_ID, Distance)
SELECT User_ID, Distance + 1
FROM dbo.fn_UserManagers(#Manager_ID)
INSERT INTO #User (User_ID, Distance) VALUES (#User_ID, 0)
RETURN
END
You need a some method to prevent your recursive query from adding User ID's already in the set. However, as sub-queries and double mentions of the recursive table are not allowed (thank you van) you need another solution to remove the users already in the list.
The solution is to use EXCEPT to remove these rows. This should work according to the manual. Multiple recursive statements linked with union-type operators are allowed. Removing the users already in the list means that after a certain number of iterations the recursive result set returns empty and the recursion stops.
with UserTbl as -- Selects an employee and his subordinates.
(
select a.[User_ID], a.[Manager_ID] from [User] a WHERE [User_ID] = #UserID
union all
(
select a.[User_ID], a.[Manager_ID]
from [User] a join UserTbl b on (a.[Manager_ID]=b.[User_ID])
where a.[User_ID] not in (select [User_ID] from UserTbl)
EXCEPT
select a.[User_ID], a.[Manager_ID] from UserTbl a
)
)
select * from UserTbl;
The other option is to hardcode a level variable that will stop the query after a fixed number of iterations or use the MAXRECURSION query option hint, but I guess that is not what you want.