How to Convert Hierarchical Data into XML in SQL Server - sql

Question

sample Input Table Details:
Expected Output:
<Geo>
<Continent Name="Asia">
<Country Name="China">
<State Name="Bejing"></State>
</Country>
<Country Name="Japan">
<State Name="Tokyo"></State>
</Country>
</Continent>
<Continent Name="Europe">
<Country Name="Germany">
<State Name="Berlin"></State>
</Country>
<Country Name="France">
<State Name="Paris"></State>
</Country>
</Continent>
</Geo>
How to convert Input relation Data as Above Output XML?

Answer 1

Something like this:
create table #continents (
continentid int, [continent name] nvarchar(100))
insert into #continents
SELECT 1, 'Asia'
UNION ALl
SELECT 2, 'Europe'
UNION ALL
SELECT 3, 'Africa'
CREATE TABLE #countries (countryid int, [country name] nvarchar(100), continentid INT)
insert into #countries
SELECT 1,'China', 1
UNION ALL
SELECT 2, 'Japan', 1
UNION ALL
SELECT 3, 'Germany', 2
UNION ALL
SELECT 4, 'France', 2
CREATE TABLE #states (stateId INT, [State Name] nvarchar(100), countryid INT)
INSERT INTO #states
SELECT 1, 'Tokya', 2
UNION ALL
SELECT 2, 'Berlin', 3
UNION ALL
SELECT 3, 'Paris', 4
UNION ALL
SELECT 4, 'Bejing', 1
select c.[Continent Name] AS [#Name]
, (
select cc.[Country Name] AS [#Name]
, (
SELECT [State Name] AS [#Name]
FROM #states ss
WHERE ss.countryId = cc.countryId
FOR XML PATH('State'), TYPE
)
FROM #countries cc
WHERE cc.continentId = c.continentId
FOR XML PATH('Country'), TYPE
)
from #continents c
for xml Path('Continent'), ROOT('Geo'), TYPE
Btw, next time, try to post data as create / insert script, instead of a screenshot, it really saves a lot of typing

Answer 2

I was just too late copying all the data....
WITH Continent AS (
SELECT 1 as Continent_ID, 'Asia' as Continent_Name
UNION ALL
SELECT 2, 'Europe'
UNION ALL
SELECT 3,'Africa'),
Country AS (
SELECT 1 as Country_ID, 'China' as Country_Name, 1 as Continent_ID
UNION ALL
SELECT 2,'Japan', 1
UNION ALL
SELECT 3, 'Germany', 2),
State AS (
SELECT 1 as State_ID, 'Tokya' as State_Name, 2 as Country_ID
UNION ALL
SELECT 2, 'Berlin', 3 )
select Continent_Name, Country_Name, State_Name
from Continent
inner join Country on Country.Continent_ID = Continent.Continent_ID
inner join State ON State.Country_ID = Country.Country_ID FOR XML AUTO, Root('Geo'), TYPE;
output (after formatting):
<Geo>
<Continent Continent_Name="Asia">
<Country Country_Name="Japan">
<State State_Name="Tokya"/>
</Country>
</Continent>
<Continent Continent_Name="Europe">
<Country Country_Name="Germany">
<State State_Name="Berlin"/>
</Country>
</Continent>
</Geo>
More info: FOR XML (SQL Server)
A SELECT query returns results as a rowset. You can optionally
retrieve formal results of a SQL query as XML by specifying the FOR
XML clause in the query. The FOR XML clause can be used in top-level
queries and in subqueries. The top-level FOR XML clause can be used
only in the SELECT statement. In subqueries, FOR XML can be used in
the INSERT, UPDATE, and DELETE statements. FOR XML can also be used in
assignment statements.