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Hi,
First of all, you did a great job in creating this example! You've really put effort into it.
I've investigated this a bit and so far I haven't used the xml portion in any way. I think it's in this stage easier to play only with the path.
What I've done:
- created a test view based on the recursive query (it's easier to handle it in the next stage)
- in the CTE I locked the root to those records having parentid 0. In the previous version all the rows acted as parents
- changed the path to build the string in reverse order to gain correct path
- changed the join in second part of the cte (it was in wrong order)
So now the path is showing better results and also the parentid is giving the previous parentid, not the original parentid.
The view looks like this:
CREATE VIEW vw_test AS
WITH ProductTree (ID, [Name], ParentID, ParentName, [Path], [xml]) AS
(
SELECT P.ID,
P.[Name],
P.ParentID,
P.ParentName,
CAST(P.ID AS Varchar(200)) AS [Path],
P.[xml] AS [xml]
FROM [TEST].[view_Xml_Product] AS P WITH (NOLOCK)
WHERE p.parentid=0
UNION ALL
SELECT P2.ID,
P2.[Name],
P2.ParentID,
P2.ParentName,
CAST(RTRIM(P3.[Path]) + '->' + cast(P2.ID as varchar(200)) AS varchar(200)) AS [Path],
(SELECT P2.ID,
P2.[Name],
P2.ParentID,
P2.ParentName,
P3.[xml] AS SubProductList
FOR XML PATH('Product'), TYPE) AS SubProductList
FROM [TEST].[view_Xml_Product] AS P2 WITH (NOLOCK)
INNER JOIN ProductTree AS P3 ON P3.ID = P2.ParentID
)
SELECT * FROM ProductTree
The next phase was to remove the rows that have 'children'. I did it in a quick and dirty way but here's the query:
SELECT *
FROM vw_test a
WHERE NOT EXISTS( SELECT 1
FROM vw_test b
WHERE b.[Path] LIKE a.[Path] + '%'
AND b.[Path] != a.[Path])
ORDER BY 5
The next step would be to eliminate the rows that are sub level row and have the same parentid. In this process those rows should be combined so that the id part should be added to the previous row. For example rows:
ID Name ParentID ParentName Path
698 SmileSport pakke 124 Special TV Group 26->124->698
699 HD Package 124 Special TV Group 26->124->699
701 Discovery Package 124 Special TV Group 26->124->701
702 Kids Package 124 Special TV Group 26->124->702
should be converted to single row having path:
26->124->698 + 699 + 701 + 702
One way to do this is to create a stored proc which uses this select and then using cursor combine rows.
One thing though. I'm quite pessimistic with the efficiency. So basically your original idea of using a function may be better when bottlenecks in that function are eliminated.
Also few observations.
- You shouldn't use 0 for the root parent id. Use NULL instead.
- Consider creating a foreign key between parentid and id.
- Don't save the parentname in the table. Fetch it when needed so you won't have possible mismatches in data and you don't have to update several places when name is changed.
Does this help you forward?
Mika
The need to optimize rises from a bad design.
My articles[ ^]
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Thanks for the reply.
My objective was too implement a solution which enables me to end up with a view, returning the required xml. Your suggestion about creating a stored procedure that uses a cursor, doesnt comply with that. Further the performance would be really bad.
I thought that my original idea of using a recursive function, and select that in a view might be the fastest solution. I merely tried to investigate whether CTE could be used to increase the performance. So for now i will stay with the recursive function.
If you find a better solution please post in this thread
Once again thanks for the effort.
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Yes, as I mentioned, I was worried about the performance too.
I wouldn't believe that the performance of a recursive function is a problem as long as it's constructed properly. I've used this techique for several years without any problems.
If something comes in my mind, I'll post it. Also if you have any questions about recursive proc implementation, open a new thread and we'll try to help.
Mika
The need to optimize rises from a bad design.
My articles[ ^]
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Whats the best sql Statement to check if a table is empty?
Thanks ONeil
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select top 1 from ... is one way. Select count(*) from is another - could be slow though if the re are a lot of records.
Bob
Ashfield Consultants Ltd
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In sql server 2k i've actually seen Count(*) return a 1 when counting an empty table, had it happen several times, cant remember why it happened anymore.
Please remember to rate helpful or unhelpful answers, it lets us and people reading the forums know if our answers are any good.
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Never seen it myself, must have been fixed in an early service pack - after all, count is one of the fundamental functions.
Bob
Ashfield Consultants Ltd
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I saw it happen in SP4, wish i could remmeber how and why it showed up.
Please remember to rate helpful or unhelpful answers, it lets us and people reading the forums know if our answers are any good.
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hi all,
i have a small code of piece which create backup of Sql server database. It works well but in some cases(when i select target path to desktop folder or documents and settings folder or program files folder) it gives following error
"Can not open backup device" & Target Path & . "Operating system error 5(Access is denied.).Backup database is terminating abnormally"
Please suggest for this error ?
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Are these folders located on the server, or are you selecting a folder in your local desktop? Have you checked whether you got write-permissions on the folder?
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eddyvluggen wrote: Are these folders located on the server, or are you selecting a folder in your local desktop?
This folder is located on local desktop(or program files or documents and settings).I have no write permission on this folder. Whether there are any method to check the permission of the folder and change the permission of the folder using vb.net ?
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sunil goyalG wrote: This folder is located on local desktop
In that case you'll need to backup on the server, and copy the backup from the server-machine to your local machine. Can you make a backup to the root of C: on the servermachine?
sunil goyalG wrote: I have no write permission on this folder.
You'll need permission. Ask your network-administrator if you can't change the permissions.
Hope this helps,
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eddyvluggen wrote: In that case you'll need to backup on the server, and copy the backup from the server-machine to your local machine
in my present case, Server and client is same
eddyvluggen wrote: You'll need permission. Ask your network-administrator if you can't change the permissions.
How can i do this thing programmatically ? It is a stand alone computer
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sunil goyalG wrote: in my present case, Server and client is same
In that case, you should be able to backup to C:\.. Have you tried whether you can backup there? It's important because it rules out any other problems, like a full harddisk and the likes.
sunil goyalG wrote: How can i do this thing programmatically ?
You can't "grant" yourself permissions from code that easily, that would be a security-hole. If you can't copy a text-file to the appropriate folder, then you also can't backup there. Can you check whether you can write a textfile to the folder that you want to backup to?
There should be a local administrator-account on the machine. That's the one that's used to set/check the permissions.
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eddyvluggen wrote: you should be able to backup to C:\.. Have you tried whether you can backup there?
i am able to take backup on root(c:\) or any other folder except(desktop,program files & documents and Settings folder)
eddyvluggen wrote: Can you check whether you can write a textfile to the folder that you want to backup to?
i am able to create any text file to above specified folder but whenever i try to create backup file then it gives error.
any suggestion ?
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Sounds like you do have write-permissions then 
It might be that the path is too long, or the spaces in the path might cause problems. Can you backup to "C:\PROGRA~1"?
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eddyvluggen wrote: Can you backup to "C:\PROGRA~1"?
No. i can not backup to this path. Also not on desktop and documents and settings folder. Except these folder i can take backup in any folder programmatically.
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Hi all,
i am doing this through vb code. After importing the data ill be moving this data in an excel sheet.
I need to know which would be the best and easy way:
1. using SSIS/DTS package.
2. using a stored procedure(Bulk insert statement).
At a time i have to move data from 2 csv into database.
Can anyone please let me know thw pros and cons of the approaches?
Thanks & Regards,
Preet
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I have done this before by reading the csv file and creating a xml file from the csv file. and then pass the xml as a string (varchar) to the stored procedure. within the stored procedure you should be able to convert the string to xml and then that will act like another table.
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Do Subsonic Generates Stored Procedure for US?
Is there any version of subsonic that do this?
If yes How?
Thanks.
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WHy not try the Subsonic web site? I bet they know.
Bob
Ashfield Consultants Ltd
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Hello,
I have some problem with search a skills like c, c#, etc. by using Containstable .
My host provider does not change noise words. Due to this we are using below quarries
If users searching a keyword like C, then query is as follows…
select id,skills,[state],metroarea,designation,cname,jobtype,city,rank FROM peoplesurge_posting as posting INNER JOIN
containstABLE(peoplesurge_posting,(skills,[state],metroarea,designation,cname,jobtype,city),'ISABOUT ("c*")') as frees ON frees.[key]= posting.[id]
Note: 'ISABOUT (C)' for this it takes as a noice word then no rusults were displayed. Due to this we adding * to keyword c. this querry gives some results but it gives wrong results i.e starting character of C
Like c, c++, c#......etc
Please resolve this problem ASAP. It’s very urgent for me.
Thanks,
Satish.
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Hi Everyone.
I have a relative simple question. I want to load an image into a SQL 2005 Database, but I dont want to write a program to do this. Is there any way that I will be able to upload the image into SQL without a Windows/Web application? Purely in SQL itself?
Your help will be greatly appreciated. I know it's properly a simple question, but I am looking for a shortcut 
Kind Regards,
Elizma
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