Query xml using sql server - sql

Question

i am new to xml queries. i have one xml like
<fields>
<fields name = "a" active ="1" mandat ="true"/>
<fields name = "a" active ="1"/>
</fields>
Now i need to find all the field names that manadt is true. How can i query xml using sql server. please help

Answer 1

Your question is not quite clear, especially the tags (sql, xml, c#-4.0), but from you question's text I take, that you need to query the XML's content within SQL-Server.
You can try it like this
DECLARE #xml XML=
N'<fields>
<fields name="a" active="1" mandat="true" />
<fields name="a" active="1" />
</fields>';
SELECT fld.value(N'#name',N'nvarchar(max)') AS Field_Name
,fld.value(N'#active',N'bit') AS Field_Active
,fld.value(N'#mandat',N'bit') AS Field_Mandant
FROM #xml.nodes(N'/fields/fields') AS A(fld)
The result
Field_Name Field_Active Field_Mandant
a 1 1
a 1 NULL
UPDATE
If you want to read the value of #name of the fields-node, where #mandat is "true", do it like this:
DECLARE #xml XML=
N'<fields>
<fields name="a" active="1" mandat="true" />
<fields name="a" active="1" />
</fields>';
SELECT #xml.value(N'(/fields/fields[#mandat="true"]/#name)[1]',N'nvarchar(max)') AS Mandant_Name
UPDATE 2: More than one <fields> with #mandat="true"
Just try my first solution with a predicate in .nodes():
DECLARE #xml XML=
N'<fields>
<fields name="a" active="1" mandat="true" />
<fields name="b" active="2" />
<fields name="c" active="3" mandat="false" />
<fields name="d" active="4" mandat="true" />
</fields>';
SELECT fld.value(N'#name',N'nvarchar(max)') AS Field_Name
,fld.value(N'#active',N'bit') AS Field_Active
,fld.value(N'#mandat',N'bit') AS Field_Mandant
FROM #xml.nodes(N'/fields/fields[#mandat="true"]') AS A(fld)
This will return only the first and the last <fields> node