RDF
RDF in a table a column for every triple
RDF has class membership
RDF is a graph (graphs do not sit well in tables)
OWL is a particular vocabulary of RDF
- relations
- cardinality
- equality
RDF vs. Relational Model
XDM = XPath and XQuery Data Model
RDF vs. XDM
XDM
- tree structured
RDF trees are more general than XDM trees
RDF relations inherent
RDF triples are tiny pieces of data
SPARQL : Protocal and RDF Query Language
matches graph patterns
sql-like syntaxis
SQL Great for finding data from tabular representations.
XQUERY Great for finding data in tree representations, can get complex when many relations have to be traversed
SPARQL Good pattern matching paradigm, especially when relationships are the poitn of the query