The document discusses exposing relational databases as Resource Description Framework (RDF). It provides an overview of relational database models (RDBM) and RDF data models. It then describes how to represent data from relational databases as RDF triples and query the semantic data using SPARQL. The key aspects covered are mapping relational schemas and data to RDF graphs, constructing RDF graphs from relational databases using SQL queries, and the advantages of representing data as RDF.

1. Exposing Relational Database
as RDF
Presented By
Shakil Ahmed (19-91472-3)
Wahiduzzaman Akanda (19-91455-3)
Afrina Talukder Mimi (19-91278-2)

2. RDBModel
 Invented by E. F. Codd at IBM in 1970.
 The model organize the data into one or more tables
consists of rows and columns.
 In relational schema there is a primary key to identify
uniquely each row in a table.
 And the foreign key roles a referential constraints
between two or more tables. Ex
Cus_id Cus_name Cus_city
001 x y

3. RDFModel
 RDF is a data model behind the semantic web
introduced by W3C.
 RDF is graph based data model.
 RDF represents the data as TRIPLE like <subject,
predicate, object>. EX.
S O
P

4. PartsofRDF
Graph
 URI: References resources.
 Literals: Describe data values
 Blank Node: Facilitate existential quantification.

5. RDFasData
Model
 RDF enables easy data integration and interoperability
between systems.
 EX. The movie “Number 1 Shakib khan” directed by
Badiul Alam Khokon from Bangladesh was released in
2010.
<s, p, o> Format:
<movie, name, Number 1 Shakib Khan>
<movie, year, 2010>
<movie, directedBy, director>
<director, name, Badiul Alam Khokon>
<director, country, Bangladesh>

6. Example  RDF Graph ?
S P O
movie name Number 1 Shakib khan
movie year 2010
movie directedBy director
director name Badiul Alam Khokon
director city Bangladesh
movie
No.1S
K
name
No.1S
K
year
director
directedBy
Badiul
BD
name
city

7. SPARQL
 Queries to the semantic web data.
 W3C standard from 15th January 2008.
 SPARQL supports generalized triple pattern <S, P, O>.
 Ex.
SELECT ?name ?year
WHERE
{
?x rdf: type vocab: Movie.
?x vocab: name ?name.
?x vocab: year ?year.
}

8. RDBvsRDF
 In RDB:
SELECT “ex:movie” +m.movie as s, “rdf:type” as p,
“vocab:Movie” as O from Movie m
 IN RDF: The triple format like,
<ex:movie, rdf:type, vocab:Movie>
<movie, name, Number 1 Shakib Khan>
<movie, year, 2010>
Answer: name: “Number 1 Shakib Khan,” year: “2010”

9. PopularRDF
Formats
 N-Triples: A text format focusing on simple parsing.
 Turtle: A text format focusing on human readability.
 Notation-3: A text format contains advanced features.
 RDF/XML: Official XML serialization of RDF.
 RDF/JSON: A proposal serialization of RDF in JSON.
 JSON-LD: Another proposal for expressing RDF in
JSON.
 RDFa: A mechanism for embedding RDFa in HTML or
XHTML.

10. RDFGraph
Construct

11. RDFGraph
Construct
 First the semantic applications access to the RDF graph
through User Interface using query expressed in SPARQL.
 Second the Syntax Parser, the main process in the steps,
analyzes and parses SP ARQL query if the query is
correct.
 Query Rewriter rewrites SP ARQL query into SQL
queries.
 In the end, SQL Assembler assembles all necessary SQL
query to create a single SQL query; then execute the SQL
query against relational databases to construct RDF
graph.
 Mapping Information another key component in the
system, which analyses the database structure and
extracts metadata from relational database using reverse
engineering technology

12. Advantagesof
RDF
 Simple but expressive data model.
 Global identifiers of all resources.
 Easier incremental data integration.
 Schema agility.
 Graph structured.

13. References
 Shufeng Zhou, "Exposing relational database as RDF,"
2010 2nd International Conference on Industrial and
Information Systems, Dalian, 2010, pp. 237-240.

14. Thank You