Database (iv)

============================= Database Design ==============================
Good database Design Advantages:
1. Save storage space for data
2. Guarantee the integrity of the data
3. Development of convenient database application system

Stage:
A. Demand analysis: Analyzing the customer's business and data processing needs
1). Collect information
2). Identify the entity
3). Identify the properties of each entity
4). Identify the relationship between entities
B. Summary design: E-R model Diagram to confirm the correctness and completeness of the requirement information
C. Detailed design: Three major paradigms audit database structure
1). Draw E-r Diagram

2). Convert the E-r diagram into a database model diagram

3). Design of standardized table with three main paradigms
D. Code writing: Physical implementation of the database, encoding implementation of the application
E. Software Testing: ...
F. Installation deployment: ...
================================= three paradigms =================================
First paradigm:
The goal of the first paradigm is to ensure the atomicity of each column
Second paradigm:
The second paradigm requires that each table only describes one thing

The third paradigm:
If a relationship satisfies 2NF and the columns other than the primary key are not passed dependent on the primary key column, the third normal form (3NF) is satisfied
That is, the third paradigm requires that the columns in the table must be directly related to the primary key and not indirectly related

Database (iv)