I want generate XML file in a hierarchical form - sql

Question

I have a table like this (Actually it contains more 6000 records)
IdIndustry | IndustryCode | IndustryName | ParentId
---------------------------------
1 | IND | Industry | NULL
2 | PHARM | Pharmacy | 1
3 | FIN | Finance | NULL
4 | CFIN | Corporate | 3
5 | CMRKT | Capital M | 4
DDL:
CREATE TABLE [dbo].[tblIndustryCodes](
[IdIndustry] [int] IDENTITY(1,1) NOT NULL,
[IndustryCode] [nvarchar](5) NULL,
[IndustryName] [nvarchar](50) NULL,
[ParentId] [int] NULL,
CONSTRAINT [PK_tblIndustryCodes] PRIMARY KEY CLUSTERED ([IdIndustry] ASC)
Inserts:
INSERT INTO [tblIndustryCodes]
([IndustryCode]
,[IndustryName]
,[ParentId])
VALUES
('IND','Industry',NULL),
('PHARM','Pharmacy',1),
('FIN','Finance',NULL),
('CFIN','Corporate Finance',3),
('CMRKT','Capital Markets',4)
And i want to generate a XML file like this(Simplified tree like structure)
<IND>
<PHARM>
</PHARM>
</IND>
<FIN>
<CFIN>
<CMRKT>
</CMRKT>
</CFIN>
<FIN>
I don't want to use recursion as it would downgrade the performance dramatically as this table has more than 60000 records in table.
I would be glad if i get the output in same format, since i will be using this output XML to send a request.
And more importantly it will be dynamic in nature.

Answer 1

Try this procedure not much sure about its efficiency as I am creating a temp table to get result
create procedure get_path as begin
DECLARE #cnt INT
DECLARE #n INT
DECLARE #tmpTable TABLE(id int,
indCode varchar(50),
indName varchar(100),
parentId int,
path varchar(500))
insert #tmpTable
select [IdIndustry], [IndustryCode], [IndustryName], [ParentId],
null from tbl
select #cnt = count(*) from #tmpTable where parentId is null
update a set a.path = CONCAT(b.indName,'/',a.indName) from #tmpTable a, #tmpTable b where b.parentid is null and a.parentid = b.id
select #n = count(*) from #tmpTable where path is null
while (#cnt < #n) begin
update a set a.path = concat(b.path, '/', b.indName, '/', a.indName) from #tmpTable a, #tmpTable b where b.path is not null and a.parentid = b.id
select #n = count(*) from #tmpTable where path is null
end
update #tmpTable set path = indName where parentid is null
select * from #tmpTable order by path
end
go
Query 1:
exec get_path
Results:
| ID | INDCODE | INDNAME | PARENTID | PATH |
-------------------------------------------------------------------------------
| 3 | FIN | Finance | (null) | Finance |
| 4 | CFIN | Corporate | 3 | Finance/Corporate |
| 5 | CMRKT | Capital M | 4 | Finance/Corporate/Corporate/Capital M |
| 1 | IND | Industry | (null) | Industry |
| 2 | PHARM | Pharmacy | 1 | Industry/Pharmacy |
Hope this helps.....
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