Database Design in Software engineering

Database, database management system (DBMS), database system real World-------------? information World--------------? Machine World
(abstract) conceptual model (transformation) data models (relationships, meshes, hierarchical models) independent of computer and computer-related data models are usually composed of a structure, data manipulation, and integrity constraints.
Hierarchical model: There is only one node with no parents, called the root node, and the other nodes have only one parent.
Mesh Model: Cancels the two limits of the hierarchical model, allowing more than one node to have no parents, and each node can have multiple parent nodes.
Relational Model: Represents the entity types and their relationships in tabular form. The basic data structure is a two-dimensional table. Each two-dimensional table is called a relationship.
Operation is mainly to check, insert, delete, change.
The logical structure of a relational model is a collection of several relational schemas.

Database Design steps: Requirements analysis, conceptual design, logical design, physical design .

Demand analysis: Generate data dictionary and flow chart.
Conceptual design: Generating a conceptual model (E-r map)
Logical Structure Design: The E-r diagram transforms into a data model (such as a relational model) to form a database logical pattern. Then form the external model of the data.
Physical design phase: Form inner mode. Select the appropriate storage structure and access methods.

Database Design in Software engineering