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1. Talal A. Alsubaie Emerging Database Technologies and Applications
2. Outline Mobile Database.
Multimedia Database.
GIS ( Geographic Information Systems ).
Talal A. Alsubaie 2
3. Mobile Database
4. Mobile Database Portable devices and wireless technology led to mobile computing.
Portable computing devices and wireless communication allowed the client to access data from any ware and any time.
There are some HW and SW problems that must be solved to make maximum exploitation of mobile computing.
i.e. Database recovery.
Hardware problems are more difficult.
Wireless coverage.
Battery.
Changes in network topology.
Wireless Transmission Speed. Talal A. Alsubaie 4
5. Mobile Computing Architecture:
Talal A. Alsubaie 5 Mobile Database
6. Mobile Ad-Hoc Network (MANET):
In a MANET, co-located mobile units do not need to communicate via a fixed network, but instead, form their own using cost-effective technologies such as Bluetooth.
In a MANET, mobile units are responsible for routing their own data, effectively acting as base stations as well as clients.
MANET must be robust enough to handle changes in network topology.
Such as arrival or departure of mobile unites.
MANET can fall under P2P architecture.
Talal A. Alsubaie 6 Mobile Database
7. Characteristics of Mobile Environments Communication latency
Intermittent connectivity
Limited battery life
Changing client location
All of these Characteristics impact data management in mobile computing.
Talal A. Alsubaie 7
8. Characteristics of Mobile Environments (2) The server may not be able to reach the client or vise versa.
We can add proxies to the client and the server to cache updates into when connection is not available.
After the connection is available proxy automatically forward these updates to its distention.
Talal A. Alsubaie 8
9. Characteristics of Mobile Environments (3) The latency involved in wireless communication makes scalability a problem.
Since latency increases the time to service each client request, so the server can handle fewer clients.
Servers can use Broadcasting to solve this problem.
Broadcast well reduces the load on the server, as clients do not have to maintain active connections to it.
For example weather broadcasting. Talal A. Alsubaie 9
10. Client mobility also poses many data management challenges:
Servers must keep track of client locations in order to efficiently route messages to them.
Client data should be stored in the network location that minimizes the traffic necessary to access it.
The act of moving between cells must be transparent to the client.
Client mobility also allows new applications that are location-based. Talal A. Alsubaie 10
11. Data Management Issues Mobile databases can be distributed under two possible scenarios:
The entire database is distributed mainly among the wired components, possibly with full or partial replication.
Management is done in fixed hosts, with additional functionalities.
The database is distributed among wired and wireless components.
Management is done in both fixed hosts and mobile units.
Talal A. Alsubaie 11
12. Data Management Issues Data distribution and replication (Cache)
Transactions models
Query processing (where data is located?)
Recovery and fault tolerance
Mobile database design
Location-based service
Division of labor
Security
Talal A. Alsubaie 12
13. Application: Intermittently Synchronized Databases The client has his own application and DBMS in his local laptop.
Do some updates locally and connect to the server via internet to get batch of updates (synchronization).
The primary characteristic of this scenario is that the clients are mostly disconnected; the server is not necessarily able reach them.
This environment has problems similar to those in distributed and client-server databases, and some from mobile databases.
Talal A. Alsubaie 13
14. Application: Intermittently Synchronized Databases Talal A. Alsubaie 14
15. Multimedia Database
16. Multimedia Databases In the years ahead multimedia information systems are expected to dominate our daily lives.
Talal A. Alsubaie 16
17. Nature of Multimedia Data and Applications DBMSs have been constantly adding to the types of data they support.
Today many types of multimedia data are available in current systems.
Text.
Graphics.
Images.
Animation.
Video.
Audio.
… Talal A. Alsubaie 17
18. Nature of Multimedia Applications Multimedia data may be stored, delivered, and utilized in many different ways.
Applications may be categorized based on their data management characteristics.
Repository applications.
A large amount of multimedia data as well as metadata is stored for retrieval purposes.
Presentation applications.
Simple multimedia viewing of video or audio data.
Collaborative work using multimedia information.
Which engineers may execute a complex design task by merging drawings, fitting subjects to design constraints, and generating new documentation, change notifications, and so forth. Talal A. Alsubaie 18
19. Data Management Issues Multimedia applications dealing with thousands of images, documents, audio and video segments, and free text data depend critically on:
Appropriate modeling of the structure and content of data.
Designing appropriate database schemas for storing and retrieving multimedia information.
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20. Data Management Issues (cont.) Multimedia information systems are very complex and embrace a large set of issues:
Modeling:
Complex Objects, dealing with large number of types of data (Graphics).
Design:
Conceptual, logical, and physical design of multimedia has not been addressed fully, and it remains an area of active research.
Storage:
Multimedia data on standard disk devices presents problems of representation, compression, mapping to device hierarchies, archiving, and buffering during the input/output operation.
DBMS has presented the BLOB type (Binary Large Object). Talal A. Alsubaie 20
21. Data Management Issues (cont.) Talal A. Alsubaie 21
22. Multimedia Database Applications
Documents and records management
Knowledge dissemination
Education and training
Marketing, advertising, retailing, entertainment, and travel
Real-time control and monitoring
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23. Geographic Information Systems (GIS)
24. Geographic Information Systems Geographic information systems(GIS):
A systematic integration of hardware and software for capturing, storing, displaying, updating manipulating and analyzing spatial data. Talal A. Alsubaie 24
25. title GIS can be divided into two formats:
Vector data represents geometric objects such as points, lines, and polygons.
Raster data is characterized as an array of points, where each point represents the value of an attribute for a real-world location.
Informally, raster images are n-dimensional array where each entry is a unit of the image and represents an attribute Talal A. Alsubaie 25
26. Talal A. Alsubaie 26
27. Characteristics of Data in GIS There are several aspects of the geographical objects need to be considered:
Location.
Temporality.
Complex Spatial Features.
Object ID.
Data Quality.
…
Talal A. Alsubaie 27
28. Characteristics of Data in GIS The geographic context, topologic relations and other spatial relationships are fundamentally important in order to define spatial integrity rules.
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29. Constraints in GIS Topology Integrity.
Deals with the behavior of features and the spatial relationship between them.
Semantic Integrity.
Deals with the meaning.
User Defined Integrity.
Business rules.
Temporal.
Punctual and Durable. Talal A. Alsubaie 29
30. Conceptual Data Models for GIS Briefly describes the common conceptual models for storing spatial data in GIS.
Some conceptual data models:
Raster data model:
Used for analytical applications.
Vector data model:
Analysis is done using a well defined set of tools. Talal A. Alsubaie 30
31. Conceptual Data Models for GIS Some conceptual data models (cont.):
Network model:
Define how lines connect to each other in a point.
Rules are stored in a connectivity table.
Example of everyday application, optimizing a school bus route.
TIN data model:
Triangular Irregular Network.
Is a vector-based approach.
models surfaces by connecting sample points as vector
of triangles. Talal A. Alsubaie 31
32. DBMS Enhancements for GIS Until the mid 1990s, GIS system was based mainly on file-based systems.
No transfer standards was defined, which limited vendors in terms of sharing.
Involved in a geo-structure and attributes was stored in DBMS.
The spatial features was kept in a file and linked to the attributes.
Could not take FULL advantage of commercial RDBMS.
Database extensions has been released by vendors like DB2 spatial extender, and OracleSpatial and OracleLocator to support GIS data.
These extensions allowed the user to store, manage, and retrieve geo-objects. Talal A. Alsubaie 32
33. GIS Standers and Operations Spatial Relationship Standard:
Equal.
Intersect.
Touch.
Cross.
Within.
… and more. Talal A. Alsubaie 33
34. GIS Standers and Operations Spatial Analysis Standard:
Distance.
Returns the shortest distance between any two points in two geometries.
Buffer.
Returns a geometry that represents all points whose distance from the given geometry is less than or equal to distance.
Convex Hull.
Union.
And more. Talal A. Alsubaie 34
35. GIS Standers and Operations
CREATE TABLE STATES (
Sname VARCHAR(50) NOT NULL,
State_shape POLYGON NOT NULL,
Country VARCHAR(50) NOT NULL,
PRIMARY KEY (Sname),
FOREIGN KEY (Country) REFERENCES COUNTRIES (Cname)
);
SELECT Sname
FROM STATS
WHERE (AREA (State_shape) > 50000)
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36. Future of GIS There are some challenges in developing GIS applications:
Data Source.
Data Model.
Standards.
Mobile GIS.
Specialized DBMS for GIS.
… Talal A. Alsubaie 36
37. Questions ?
38. Thanks