1. Concepts of Database Management, Fifth Edition
Chapter 9:
Database Management Approaches

2. Objectives Describe distributed DBMSs Discuss client/server systems
Define data warehouses and explain their structure and access
Discuss the general concepts of object- oriented DBMSs
Concepts of Database Management, 5th Edition

3. Objectives Summarize the impact of Web access to databases
Provide a brief history of database management
Describe the network and hierarchical data models
Concepts of Database Management, 5th Edition

4. Distributed Databases
Computers at various sites
Connected with communications network
Distributed database is single logical database physically divided among networked computers
DDBMS supports and manipulates distributed databases
Concepts of Database Management, 5th Edition

5. Figure 9.1: Communications Network
Concepts of Database Management, 5th Edition

6. Characteristics of Distributed DBMSs
Homogeneous
Same local DBMS at each site
Heterogeneous
At least two sites with different DBMSs
Concepts of Database Management, 5th Edition

7. Characteristics of Distributed DBMSs (con’t.)
Location transparency
User feels as though entire database is at their site
Replication transparency
User unaware of behind the scenes replication of the data
Fragmentation transparency
Logical object divided among various locations
Concepts of Database Management, 5th Edition

8. Unfragmented Parts Table
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9. Fragmented Parts Table
Concepts of Database Management, 5th Edition

10. Advantages of Distributed Databases
Local control of data
Possible legal reasons for local control over data used in a particular geographic region
Increased database capability
Added system availability
Though parts of a database may not be accessible, transactions can still occur, increasing overall availability of the database
Added efficiency
Smaller tables are faster to query
Concepts of Database Management, 5th Edition

11. Disadvantages of Distributed Databases
Problems updating replicated data
More complex query processing
More complex treatment of concurrent update
More complex recovery measures
More difficult management of the data dictionary
More complex database design
Concepts of Database Management, 5th Edition

12. Rules for Distributed Databases
Local autonomy
No reliance on a central site
Continuous operation
Location transparency
Fragmentation transparency
Replication transparency
Concepts of Database Management, 5th Edition

13. Rules for Distributed Databases (con’t.)
Distributed query processing
Distributed transaction management
Hardware independence
Operating system independence
Network independence
DBMS independence
Concepts of Database Management, 5th Edition

14. Client-Server Systems
Tiered approach to developing systems
Typical systems will implement two tiers
Client
Server
Server manages all access to data
Client consults server for most processing
Some systems almost totally abstract the client from any processing by introducing a middle tier to handle all logic or processing
Concepts of Database Management, 5th Edition

15. Client/Server Systems
Figure 9.4:
Client/Server Systems
Concepts of Database Management, 5th Edition

16. Figure 9.5: Two-Tier Client/Server Architecture
Concepts of Database Management, 5th Edition

17. Figure 9.6: Three-Tier Client/Server Architecture
Concepts of Database Management, 5th Edition

18. Advantages of Client/Server Systems
Lower network traffic
Improved processing distribution
Thinner clients
Greater processing transparency
Concepts of Database Management, 5th Edition

19. Advantages of Client/Server Systems (con’t.)
Increased network, hardware, and software transparency
Improved security
Decreased costs
Increased scalability
Concepts of Database Management, 5th Edition

20. Triggers and Stored Procedures
Actions that occurs automatically in response to a particular database operation
Created by programmers
Use special SQL statements
Stored Procedures
Collection of SQL statements compiled and optimized by DBMS
Improves performance
Concepts of Database Management, 5th Edition

21. Data Warehouses
Subject-oriented, integrated, time-variant, nonvolatile collection of data in support of management’s decision-making process
Used for analysis of existing data
Resolves performance issues suffered by operational RDBMSs and OLTPs
Concepts of Database Management, 5th Edition

22. Data Warehouse Architecture
Figure 9.7:
Data Warehouse Architecture
Concepts of Database Management, 5th Edition

23. Data Warehouse Structure
Figure 9.8:
Data Warehouse Structure
Concepts of Database Management, 5th Edition

24. On-Line Analytical Processing
Optimized to work with data warehouses
Used to answer questions
Allows users to perceive data as a multidimensional data cube
Slice and dice
Drill down
Roll Up
Data mining
Concepts of Database Management, 5th Edition

25. Data Cube Representation
Figure 9.9:
Data Cube Representation
Concepts of Database Management, 5th Edition

26. Slicing on Time Dimension
Figure 9.11:
Slicing on Time Dimension
Concepts of Database Management, 5th Edition

27. Dicing on Part Dimension
Figure 9.12:
Dicing on Part Dimension
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28. Rules for OLAP Systems Multidimensional conceptual view Transparency
Accessibility
Consistent reporting performance
Client/server architecture
Generic dimensionality
Concepts of Database Management, 5th Edition

29. Rules for OLAP Systems Dynamic sparse matrix handling
Multiuser support
Unrestricted, cross-dimensional operations
Intuitive data manipulation
Flexible reporting
Unlimited dimensions and aggregation levels
Concepts of Database Management, 5th Edition

30. Object-Oriented DBMS (OODBMS)
System in which data and methods operating on that data are encapsulated into objects
Store graphics, drawings, video, sound, and other complex objects called binary large objects (BLOBs)
General concepts
Objects and classes
Methods and messages
Inheritance
Concepts of Database Management, 5th Edition

31. Unified Modeling Language (UML)
Models various aspects of software development for OO systems
Includes several types of diagrams
Class
Use Case
State
Sequence
Activity
Collaboration
Component
Concepts of Database Management, 5th Edition

32. Figure 9.19: Class Diagram for Premiere Products
Concepts of Database Management, 5th Edition

33. Class Diagram with Constraints
Figure 9.20:
Class Diagram with Constraints
Concepts of Database Management, 5th Edition

34. Generalization and a Constraint
Figure 9.21:
Class Diagram with a
Generalization and a Constraint
Concepts of Database Management, 5th Edition

35. Rules for OODBMSs Complex objects Object identity Encapsulation
Information hiding
Types of classes
Inheritance
Late binding
Concepts of Database Management, 5th Edition

36. Rules for OODBMSs (con’t.)
Computational completeness
Extensibility
Persistence
Performance
Concurrent update support
Recovery support
Query facility
Concepts of Database Management, 5th Edition

37. Web Access to Databases
Electronic Commerce
Conducting business on the Internet
Business to Business
Business to Consumer
Internet facilitating better access to data
Extensible Markup Language (XML)
Key technology to data interchange between systems
Concepts of Database Management, 5th Edition

38. Figure 9.22: Web Access to Databases
Concepts of Database Management, 5th Edition

39. History of Database Management
Early systems
GUAM, DL/I, IMS, IDS, IDMS
Relational products
DB2, Oracle, Sybase, Paradox, dBASE, Access, MySQL, SQL Server
OODBMSs
Gemstone, Objectivity/DB, Versant
ORDBMSs
Concepts of Database Management, 5th Edition

40. Hierarchical and Network Databases
Data models have two components, structure and operations
Structure is how users perceive data to be structured
Operations are facilities given to users to interact with data
Users perceive a network model database as a collection of record types and relationships
Users perceive a hierarchical model as a collection of hierarchies or trees
Concepts of Database Management, 5th Edition

41. Summary
Distributed databases physically fragment a database across many parts of a DBMS, but they must maintain reasonable transparency
Most applications built around a DBMS will use a client-server architecture, involving at least two tiers, but more typically three
Data warehouses are specialized DBMS products that allow users to view the data in more than two dimensions, typically three
Concepts of Database Management, 5th Edition

42. Summary (con’t.)
Object Oriented databases provide an encapsulated view by merging data with their operations, fitting with modern programming architectures
Web access is common way to access data in a DBMS
Hierarchical and network data models are two models of how users perceive a DBMSs structure and operation
Concepts of Database Management, 5th Edition