1. IS432 Semi-Structured Data
Lecture 6:
XML Mapping to Object/Relational Databases
Dr. Gamal Al-Shorbagy

2. -----------------------------
Table Based Mapping
<A>
<B>
<C>ccc</C>
<D>ddd</D>
<E>eee</E>
</B>
<C>fff</C>
<D>ggg</D>
<E>hhh</E>
</A>
Table A
C D E
ccc ddd eee
fff ggg hhh

3. Table Based Mapping <Tables> <Table_1> <Row>
<Column_1>...</Column_1> ...
<Column_n>...</Column_n>
</Row>
...
<Column_1>...</Column_1>
</Table>
<Tables>
<Table_1>
<Row>
<Column_1>...</Column_1>
...
<Column_n>...</Column_n>
</Row>
</Table_1>
<Table_n>
<Column_m>...</Column_m>
</Table_n>
</Tables>

4. Table Based Mapping Advantages Disadvantages Simplicity
Easy to write code
Easy to transfer data between XML and Database
Disadvantages
Too simple to work with complex XML documents
Does not preserve physical structure
Such as character and entity references,
CDATA sections,
Character encodings
The document type or DTD
Comments, or processing instructions.

5. XML-Object-Relational Mapping
RDB
<XML/>
Instance

6. XML-Object-Relational Mapping

7. XML-Object-Relational Mapping
Instance
RDB
DTD
DTD
Object Schema
Relational Schema

8. Object Relational Mapping

9. Object Relational Mapping

10. Object Relational Mapping
Object SalesOrder{
number =1234;
customer = “Abdullah”;
date = ;
items = {pointer to Item objects}; }
Object Item{
number =1;
item = “CD-ROM”;
Quantity = 1;
price = 25; }
Object Item{
number = 2;
item = “DRAM”;
Quantity = 1;
price = 65; }

11. Object Relational Mapping
SalesOrder
number
customer
date
1234
Abdullah ….
Items
sonumber
number
Item
quantity
price
1234 1
CD-ROM 25 2
DRAM 65

12. Sub Elements - Composition

13. Element Occurrence Constraints

14. Object-Relational Mapping

15. Mapping Complex Content Models
<!ELEMENT A (B?, (C | ((D | E | F | G)*, (H | I)+, J?)))>

16. Mapping Sequences

17. Mapping Choices

18. Mapping Repeated Children

19. Mapping Groups

20. Mapping Attributes

21. Mapping Attributes

22. Take Home Quiz
Create XML Schema/XML to store data in following relational database tables.
Students
Name ID
Book_ID
Ahmad
0001
1111
Ali
0002
1112
Hassan
0003
1113
Books
Book_ID
Title
Author
1111
XML for Dummies
Ahmad Ali
1112
Semi Structured Data
1113
XML in Summer

23. Thanks