Download 4. MQP presentation

Rainbow - Bridging XML and Relational Databases:
Design, Implementation, and Evaluation
MQP Project Members:
MQP Advisor:
Tien Vu,
Prof. Elke A. Rundensteiner, PhD
Mirek Cymer,
Sponsor:
John Lee
Verizon Laboratories Incorporated
04-19-2001
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HTML vs. XML
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XML Data Management by RDBMS

Microsoft, IBM, Informix, Oracle,...

Advantages:




Matured database tools available.
Efficient query and analysis tools.
Easy integration with existing business databases.
Issues:



Map between XML and Relational Model.
Update Propagation.
Query Translation and Optimization.
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Traditional System Architecture
XML
Query
User
XML
Legend
XML Query Engine
XML
Data
RDBMS
Sub
system
XML Manager
XML
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Motivation for Flexible Mapping
Query Performance varies with respect to how data is mapped.

Car
iid
pid
1
0
…
…
SELECT * FROM model;
Make
iid
pid
Value
2
1
Ford
…
…
…
SELECT model FROM car WHERE make = ‘Ford’;
car
Model
iid
pid
Value
3
1
Mustang
…
…
…
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iid pid
Make
Model
Year
1
0
Ford
Mustang 2001
…
…
…
…
…
Year
iid
pid
Value
3
1
2001
…
…
…
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Rainbow Architecture
XML
Query
User
XML
Legend
XML Query Engine
Restructuring Subsystem
DTD Manager
DTD

RDBMS
XML Manager
XML
Data
Sub
system
XML
Flexible mapping = fixed Mapping + restructuring
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Goals of our MPQ

Target:


Implement and evaluate restructuring subsystem within
the large-scale Rainbow system.
Methodology:





Learn about the database technologies and web tools.
Translate research ideas to software system design.
Practice software engineering techniques.
Design an experimental test plan and test bed.
Conduct performance study and analysis.
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Rainbow Restructuring Subsystem
XML
Query
User
XML
Legend
XML Query Engine
Sub
system
Data
Restructuring Subsystem
Process
DTD Manager
DTD
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XML Manager
XML
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Rainbow Restructuring Subsystem
XML
Query
User
XML
Legend
XML Query Engine
Restructuring
Sub
system
Mapping
Data
Restructure
Operator
Library
Restructurer
Process
DTD Manager
DTD
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XML Manager
XML
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Restructuring Library
Optimization
 Pushup/Pushdown Attribute
 Pushup/Pushdown Nesting
 Organization
 Rename Item/Attribute
 Completeness
 SwitchNesting
 Split/Merge Nesting
 Reference/Dereference

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Pushup Attribute Operator
A
A
B
Push-up
B
a
b
CREATE VIEW new.A (<all-columns>, a) AS
SELECT A.<all_columns>, B.b
FROM old.A, old.B
WHERE B.pid = A.iid
CREATE VIEW new.B (<all-columns-but-b>) AS
SELECT B.<all-columns-but-b>
FROM old.B
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Instantiated Restructuring Operators

Mapping = Operators + Parameters.
pushUpAttribute(‘Model’, ‘Value’, ‘Car’, ‘Model’);
Car
Value
Car
Value
Parent
Model
Parent
Mustang
Model
Value
Parent
Mustang
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Rainbow Implementation


Development Tools
 Java: Visual Café2,
Javadocs, JAVA2
 Oracle 8i, XML 4J,
JDBC1.2, SQL Queries
Code Facts
 44 total system classes
 17 classes created by
Rainbow
 19 classes extended
 8 classes reused
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# of Classes
17
19
8
New
Reused
Extended
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Screen Shot of Rainbow
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Setup for Rainbow Evaluation

Experimental

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Database Server:
 Oracle 8i on a PII 300MHz, 256MB, Microsoft NT Server
Client:
 Pentium 233MHz, 128MB, Microsoft NT Workstation
Data


Designed a DTD
Generated XML using IBM’s
XML-Generator
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DTD CONTENT:
<!ELEMENT one (two+)>
<!ELEMENT two (three)>
<!ELEMENT three (four)>
<!ELEMENT four (five)>
<!ELEMENT five (six)>
<!ELEMENT six (seven)>
<!ELEMENT seven EMPTY>
<!ATTLIST seven attribute #REQUIRED>
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Query Performance Evaluation
Time of Join Query (data-size=22Mb)
Query Time (s)
40
30
20
10
0
0
1
2
3
4
5
6
7
# of PushUpAttribute
Time of Join Query
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Overhead Cost
Restructure Time (s)
Time of overhead (datasize=22Mb)
350
300
250
200
150
100
50
0
0
1
2
3
4
5
6
7
# of pushUpAttribute
overhead time
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MQP Accomplishments

Technical accomplishments
Implemented functional prototype system
 Confirmed feasibility of Rainbow architecture
 Designed automated test bed
 Conducted preliminary experimental studies


Knowledge acquired
OO, Java, JDBC, SQL, RDBMS, XML, DTD
 Teamwork & S/W Engineering & Software Reuse
 Logistics of setting up and running experiments

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Potential Future Work
XML query translation to SQL
 Experiment with test plans and test beds to realize
the full potential of the restructuring component.

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Special thanks to:
Prof. Elke A. Rundensteiner
Ph.D. Xin Zhang
Visit Rainbow at http://davis.wpi.edu/dsrg/TJM/
Project Members:
Tien Vu, Mirek Cymer, John Lee
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