Some more about XML:
Well-formed XML conforms to syntax rules, while valid XML conforms to syntax and a DTD.
- easy to share
- no middleware
- greater flexibility
- minimal overhead
While disadvantages include:
- There is no optimization of queries.
- It is not as rigid as a DBMS.
- There is no built-in security model.
- It doesn’t have the ACID properties, but a DBMS does.
- The number of users is a (performance) consideration.
- Static or dynamic content is another consideration for determining when appropriate to use.
- Data is not normalized, duplications are not eliminated.
- XML is case-sensitive.
It is difficult to express a relationship between non-hierarchical nodes.
Element vs Attributes:
i. attributes when you’re CERTAIN the element will only have 1 value associated with it.
ii. you are certain that the attributes will never need to be expressed in terms of children.
iii. otherwise, make it an element.
Some advantages of XML include its portability, ease of sharing, lack of middle-ware, greater flexibility, and minimal overhead.
While disadvantages include no optimization of queries, not as rigid as a DBMS, no built-in security model, it isn’t ACID like DBMS, # users a consideration, static or dynamic?, as well as being redundant and verbose.