This might genereate be a better version of your XML.

This might generate a better version of your XML.

declare @T table
(
  ID  int,
  Name varchar(10),
  Age int,
  HairColor varchar(10),
  HasCar bit
);

insert into @T(ID, Name, Age, HairColor, HasCar) values
(1, 'Bert' , 25, 'blonde'  , 1),
(2, 'Agnes', 61, 'white'   , 0),
(3, 'Diane', 43, 'brunette', 1);

select row_number() over(order by T.ID) as '@Group',
       T.ID as 'MyTag/@Value',
       null,
       T.Name as 'MyTag/@Value',
       null,
       T.Age as 'MyTag/@Value',
       null,
       T.HairColor as 'MyTag/@Value',
       null,
       T.HasCar as 'MyTag/@Value'
from @T as T
for xml path('MyGroupingTag'), root('MyRootElement');

declare @T table
(
  ID  int,
  Name varchar(10),
  Age int,
  HairColor varchar(10),
  HasCar bit
);

insert into @T(ID, Name, Age, HairColor, HasCar) values
(1, 'Bert' , 25, 'blonde'  , 1),
(2, 'Agnes', 61, 'white'   , 0),
(3, 'Diane', 43, 'brunette', 1);

select row_number() over(order by T.ID) as '@Group',
       T.ID as 'MyTag/@Value',
       null,
       T.Name as 'MyTag/@Value',
       null,
       T.Age as 'MyTag/@Value',
       null,
       T.HairColor as 'MyTag/@Value',
       null,
       T.HasCar as 'MyTag/@Value'
from @T as T
for xml path('MyGroupingTag'), root('MyRootElement');

This might genereate be a better version of your XML.

select row_number() over(order by T.ID) as '@Group',
       'ID' as 'MyTag/@Name',
       T.ID as 'MyTag/@Value',
       null,
       'Name' as 'MyTag/@Name',
       T.Name as 'MyTag/@Value',
       null,
       'Age' as 'MyTag/@Name',
       T.Age as 'MyTag/@Value',
       null,
       'HairColor' as 'MyTag/@Name',
       T.HairColor as 'MyTag/@Value',
       null,
       'HasCar' as 'MyTag/@Name',
       T.HasCar as 'MyTag/@Value'
from @T as T
for xml path('MyGroupingTag'), root('MyRootElement');

Result:

<MyRootElement>
  <MyGroupingTag Group="1">
    <MyTag Name="ID" Value="1" />
    <MyTag Name="Name" Value="Bert" />
    <MyTag Name="Age" Value="25" />
    <MyTag Name="HairColor" Value="blonde" />
    <MyTag Name="HasCar" Value="1" />
  </MyGroupingTag>
  <MyGroupingTag Group="2">
    <MyTag Name="ID" Value="2" />
    <MyTag Name="Name" Value="Agnes" />
    <MyTag Name="Age" Value="61" />
    <MyTag Name="HairColor" Value="white" />
    <MyTag Name="HasCar" Value="0" />
  </MyGroupingTag>
  <MyGroupingTag Group="3">
    <MyTag Name="ID" Value="3" />
    <MyTag Name="Name" Value="Diane" />
    <MyTag Name="Age" Value="43" />
    <MyTag Name="HairColor" Value="brunette" />
    <MyTag Name="HasCar" Value="1" />
  </MyGroupingTag>
</MyRootElement>

The null between columns in the column list is there to separate MyTag into different elements.