Question

This is an XML exercise.

Change the format of the appUsers.xml document (see below) to remove the attributes and use elements to store the data.

Then explain the main disadvantage to having the file in the format you’ve just created.

Bear in mind that data is often transmitted across networks rather than just being consumed where it is stored.

appUsers.xml:

<applicationUsers>
<user firstName=”Joe” lastName=”Fawcett” />
<user firstName=”Danny” lastName=”Ayers” />
<user firstName=”Catherine” lastName=”Middleton” />
</applicationUsers>

Answer 1

appUsers.xml

<?xml version="1.0"?>
<!DOCTYPE ApplicationUsers
[
<!ELEMENT ApplicationUsers (user1,user2,user3)>
<!ELEMENT user1 (firstName1,lastName1)>
   <!ELEMENT user2 (firstName2,lastName2)>
   <!ELEMENT user3 (firstName3,lastName3)>

   <!ELEMENT firstName1 (#PCDATA)>
<!ELEMENT lastName1 (#PCDATA)>

   <!ELEMENT firstName2 (#PCDATA)>
<!ELEMENT lastName2 (#PCDATA)>

<!ELEMENT firstName3 (#PCDATA)>
<!ELEMENT lastName3 (#PCDATA)>

]>
<ApplicationUsers>
<user1>
    <firstName1>Joe</firstName1>
    <lastName1>Fawcett</lastName1>
  
</user1>

   <user2>
    <firstName2>Danny</firstName2>
    <lastName2>Ayers</lastName2>
  
</user2>

   <user3>
    <firstName3>Catherine</firstName3>
    <lastName3>Middleton</lastName3>
  
</user3>

</ApplicationUsers>

VALIDATION

Answer 2

Hi,

Please look at the appUsers.xml after modifications according to above mentioned rule.

<applicationUsers>
<user>
<firstName>Joe</firstName>
<lastName>Fawcett</lastName>
</user>
<user>
<firstName>Danny</firstName>
<lastName>Ayers</lastName>
</user>
<user>
<firstName>Catherine</firstName>
<lastName>Middleton</lastName>
</user>
</applicationUsers>

1. The Main disadvantage of providing the data in the format of elements is "It increases the number of lines if you have many entities to model" so your file looks clumsy after everything gets added.
2. If certain entity is part of Data, then it is preferable to use element. For example, customer name, customer id are an essential part of the customer data.
3. Now if you want to convey additional information about the data which is not really a part of data(METADATA) then it is better to make it an attribute.