,Contents
Advantage and Disadvantages of DBMS ................................................................................................................................. 4
Advantage of DBMS ............................................................................................................................................................ 4
1. Improved data sharing: ............................................................................................................................................... 4
2. Improved data security: .............................................................................................................................................. 4
3. Better data integration: .............................................................................................................................................. 4
4. Minimized data inconsistency: .................................................................................................................................... 4
5. Improved data access:................................................................................................................................................. 5
6. Improved decision making: ......................................................................................................................................... 5
Disadvantage of DBMS........................................................................................................................................................ 5
1. Increased costs: ........................................................................................................................................................... 5
2. Management complexity: ........................................................................................................................................... 5
3. Maintaining currency: ................................................................................................................................................. 5
4. Frequent upgrade/replacement cycles: ...................................................................................................................... 5
Functions of a DBMS: .............................................................................................................................................................. 8
Chapter 2 Data models ......................................................................................................................................................... 10
Features ........................................................................................................................................................................ 14
Terminology ................................................................................................................................................................ 15
Advantages and disadvantages ........................................................................................................................................ 15
Advantages .................................................................................................................................................................. 15
Disadvantages ............................................................................................................................................................. 16
Chapter 3 The ER Model ....................................................................................................................................................... 19
Chapter 4 Entity Relationship Modelling .............................................................................................................................. 23
Chapter 5 Advanced Data modeling ..................................................................................................................................... 24
Chapter 6 Database Normalization ....................................................................................................................................... 25
Chapter 7 SQL........................................................................................................................................................................ 29
Chapter 8 p390 SQL2 ............................................................................................................................................................ 34
, ➔ Data is raw facts, which have no meaning and have not been interpreted yet.
➔ Information is data that has been processed and interpreted that is meaningful and useful.
➔ Information needs context to be reveal meaning, e.g a temp of 105 needs units (F or C), peripheral vs
core temp etc.
➔ Data management is the process of handling operations on data such as storage, retrieval,
modification, addition and removal.
➔ Knowledge is the body of information about a topic
➔ A database is a structure that contains raw data, along with it’s metadata and is managed by a DBMS.
Advantage and Disadvantages of DBMS ................................................................................................................................. 4
Advantage of DBMS ............................................................................................................................................................ 4
1. Improved data sharing: ............................................................................................................................................... 4
2. Improved data security: .............................................................................................................................................. 4
3. Better data integration: .............................................................................................................................................. 4
4. Minimized data inconsistency: .................................................................................................................................... 4
5. Improved data access:................................................................................................................................................. 5
6. Improved decision making: ......................................................................................................................................... 5
Disadvantage of DBMS........................................................................................................................................................ 5
1. Increased costs: ........................................................................................................................................................... 5
2. Management complexity: ........................................................................................................................................... 5
3. Maintaining currency: ................................................................................................................................................. 5
4. Frequent upgrade/replacement cycles: ...................................................................................................................... 5
Functions of a DBMS: .............................................................................................................................................................. 8
Chapter 2 Data models ......................................................................................................................................................... 10
Features ........................................................................................................................................................................ 14
Terminology ................................................................................................................................................................ 15
Advantages and disadvantages ........................................................................................................................................ 15
Advantages .................................................................................................................................................................. 15
Disadvantages ............................................................................................................................................................. 16
Chapter 3 The ER Model ....................................................................................................................................................... 19
Chapter 4 Entity Relationship Modelling .............................................................................................................................. 23
Chapter 5 Advanced Data modeling ..................................................................................................................................... 24
Chapter 6 Database Normalization ....................................................................................................................................... 25
Chapter 7 SQL........................................................................................................................................................................ 29
Chapter 8 p390 SQL2 ............................................................................................................................................................ 34
, ➔ Data is raw facts, which have no meaning and have not been interpreted yet.
➔ Information is data that has been processed and interpreted that is meaningful and useful.
➔ Information needs context to be reveal meaning, e.g a temp of 105 needs units (F or C), peripheral vs
core temp etc.
➔ Data management is the process of handling operations on data such as storage, retrieval,
modification, addition and removal.
➔ Knowledge is the body of information about a topic
➔ A database is a structure that contains raw data, along with it’s metadata and is managed by a DBMS.
