The Database Development Process Flashcards
What are the 8 stages of the database development lifecycle?
- Database Planning
- Systems Definition
- Requirements Definition and Analysis
a. Conceptual Design
b. Logical Design
c. Physical Design - Application Design
- Implementation
- Data Conversion and Loading
- Testing
Operational Maintenance
What is database planning?
Planning how to do the project
- How does the enterprise work
- Enterprise data model
What is systems definition
Specifying scope and boundaries
- Users
- Application areas
How does the system interfere with other organisational systems
What is requirements definition and analysis
Collection and analysis of requirements for the new system
1. Construction of a model of the data used in the database
a. independent of all physical considerations
b. Data models
i. ER diagrams
- Construction of a (relational) model of the data based on the conceptual design
a. Independent of a specific database and other physical considerations
What is application design?
Done in conjunction with design
Design of the interface and application programs that use and process the database
What is implementation?
The physical realisation of the database
Implementation of the design
What is data conversion and loading?
-Transfer existing data into the database
- Conversion from old systems
- Non trivial task
What is testing
Running the database to find errors in the design/setup (both at a physical level and a logical level)
Issues
- Performance
- Robustness
- Recoverability
- Adaptability
What is operational maintenance?
The process of monitoring and maintaining the database system following its commissioning
- Handling new requirements
- Handling changes to requirements
What are some character types in MySQL?
- CHAR(M): A fixed-length string, right-padded with spaces. The range of M is 0 to 255.
- VARCHAR(M): A variable-length string. The range of M is 1 to 65535. (its 255 max. in MySQL 4).
- BIT, BOOL, CHAR: CHAR(1).
- BLOB, TEXT: up to 65535 bytes (for blob) or characters (for text).
- ENUM (‘value1’,’value’,…) up to 65,535 members.
- SET (‘value1’,’value2’, …) up to 64 members.
What are some integer types in MySQL?
- TINYINT[(M)]: Signed (-128 to 127) Unsigned(0 to 255)
- SMALLINT[(M)]: Signed (-32768 to 32767) Unsigned (0 to 65535)
- MEDIUMINT[(M)]: Signed (-8388608 to 8388607) Unsigned (0 to 16777215)
- INT[(M)] / INTEGER[(M)]: Signed (-2147483648 to 2147483647) Unsigned (0 to 4294967295)
-
BIGINT[(M)]: Signed(-9223372036854775808 to 9223372036854775807) Unsigned(0 to
18,446,744,073,709,551,615)
What are some real type data in MySQL
-
FLOAT[(M,D)]: single-precision, allowable values: -
- 3.402823466E+38 to -1.175494351E-38, 0, and 1.175494351E-38 to 3.402823466E+38.
- M = display width, D = number of decimals.
-
DOUBLE[(M,D)] / REAL[(M,D)]: double-precision, allowable values: -
- 1.7976931348623157E+308 to -2.2250738585072014E-308, 0, and
2.2250738585072014E-308 to 1.7976931348623157E+308.
- 1.7976931348623157E+308 to -2.2250738585072014E-308, 0, and
-
DECIMAL[(M[,D])]: fixed-point type. An unpacked floating-point number. Stored as string. Good for
MONEY!
What are some time and date type data in MySQL?
- DATE 1000-01-01 to 9999-12-31
- TIME -838:59:59 to 838:59:59
- DATETIME 1000-01-01 00:00:00 to 9999-12-31 23:59:59
- TIMESTAMP 1970-01-01 00:00:00 - ~ 2037 Stored in UTC, converted to local
- YEAR[4] 1901 to 2155 - A useful function in MySQL: NOW();
What is conceptual design?
Construction of a model of the data used in the database
- independent of all physical considerations
- Data models
- ER diagrams
What is logical design?
Construction of a (relational) model of the data based on the conceptual design
- Independent of a specific database and other physical considerations
