In the advanced article, we learned many advanced SQL functions, including null value processing, join queries, subqueries, set operations, general table expressions, advanced grouping options, window functions, and row pattern recognition in the previous article. These features can help us achieve various complex data analysis and report functions.
Starting from today, we will enter the study of the development chapter to understand how to design the database model, manage the table and the data in the operation table, understand the database transaction, index, view and write server-side programs. First, let's take a look at how to design the structure of the database.
Database design process
Database design is the process of organizing and structuring data. The key issue is the design of the data model . A good design is essential to a database system. It can reduce data redundancy in the system, ensure data consistency and integrity, and is easy to maintain and expand.
The common database design process mainly includes the following steps:
- Demand analysis , collect and analyze users' data storage and processing needs of the system, and record the data objects that need to be stored.
- Conceptual design , create a conceptual model of the database according to requirements. That is to find out the entities, the attributes of the entities, and the relationships between the entities. The result is usually an Entity-Relationship Diagram.
- Logical design , design the relational schema of the database, including defining the primary key and foreign key of the table. In addition, the relationship model needs to be optimized through standardized processes to reduce data redundancy and maintain data consistency and integrity.