Summary: How to Display Data on Web Pages
120021. Course Summary
In the previous courses, we learned the basic concepts of data management, including the role of databases, relational databases like MySQL, and the basic usage of SQL statements. We also learned how to use data management tools such as MySQL and Navicat for data management operations, as well as methods and techniques for reading documentation from beginner tutorials. By reading the documentation, we learned how to perform data insertion, deletion, modification, and querying operations in MySQL using SQL statements, became familiar with data association queries and the use of views, and understood the concept of MySQL stored procedures. This knowledge provides a foundation for our understanding of the data management process.
However, data management operations cannot be limited to the database alone. We need to present data on web pages so that users with different permissions can view, add, modify, and delete data. So, how do we display data on web pages?
2. From Database to Web Page: Overview of Data Flow
The Importance of Permission Control
Before understanding the data management process, we need to grasp a concept: permission control. Permission control refers to determining user access rights to system resources and restricting their operational scope within the system. In data management, permission control is crucial. Through permission control, it ensures that only authorized users can access, modify, or delete specific data, preventing unauthorized access and malicious operations, thereby protecting the security and integrity of the data.
Overview of Data Flow
Displaying data on web pages is a data flow from the database to the user's browser, which involves collaboration between the front end and the back end. First, data is stored in the back-end database, then processed by back-end applications, and finally presented to authorized users in the form of web pages.
To better understand the data flow, let's explain two key concepts: front end and back end.
- Concepts of Front End and Back End
The front end is the part that users interact with directly, akin to the facade and display window of a website. For example, when we open a web page in a browser, we see buttons, forms, images, etc., on the page. When you click on a product on a shopping website and enter the product detail page, what you see is the front-end page.
The back end, on the other hand, is responsible for processing data and logic, similar to the brain and logistics center of the website. It typically runs on a server and is responsible for receiving user requests, processing data, executing logical operations, and returning results to be displayed on the front-end page. For instance, in a social media application, the back end handles user logins, message sending and receiving, notifications, etc., and the results of these operations are displayed to users through the front-end page.
- Front-End Work: Presenting Data and Implementing Interaction
On the front end, data is usually presented to users in the form of web pages. This includes using technologies such as HTML, CSS, and JavaScript to build user interfaces and implementing interactions with the back end through technologies like Ajax, such as real-time data updates or responding to user actions.
- Back-End Work: Storing and Processing Data
On the back end, data is stored in the database and processed by back-end applications. The back-end application typically runs on a server, receives requests from the front end, executes corresponding logical operations, and then returns the processing results to the front end.
For example:
When you register an account on a web page, fill out a form, and click "Submit," the front end sends the data from the form to the back end for processing. After receiving the form data sent from the front end, the back end stores this data in the database and generates a user account, setting account permissions.
If you want to gain a deeper understanding of the principles from the database to the web page, we recommend studying our Course 002: Introduction to Application Development. Through this course, you will further learn how to effectively present data from the database on web pages and understand more knowledge related to application development, thereby better mastering data management and web presentation skills.
3. Introduction to the Next Course and Learning Path
Now that you have completed the introductory course on data management, we hope that this course has helped you establish an understanding of data management, alleviated your fears of learning programming and data, and adjusted your previous incorrect learning methods through reading documentation.
Overview of Learning Content for 103
In the next phase, you will delve into the practical aspects of database management in application development, focusing on data table structure design, data cleaning, and import. First, understand the basic principles of database design and learn to use operations such as indexes, views, triggers, and transactions to optimize data table design, improve data query speed, and ensure data integrity. On this basis, through specific case analyses, understand how to apply the basic principles of data design and the functions of databases in application development to support application program requirements. Understand the importance of data cleaning, learn methods for data cleaning, and clean non-compliant data to meet design requirements, ensuring data quality and usability, and effectively importing cleaned data into the database.
Knowledge to Preview
Database Design Principles: Understand the basic principles of database design, including data normalization, management of redundancy and consistency, and design of indexes and keys.
Index Optimization: Learn how to design and use indexes to improve database query performance, including understanding different types of indexes and how to optimize query statements to fully utilize indexes.
Application of Views: Gain a deeper understanding of the uses of views and learn how to use views to simplify application logic development.
Creation of Triggers: Master the concept and working principles of triggers, and learn how to create triggers to automatically execute specific operations when certain events occur in the database.
Transaction Processing: Learn the concepts and characteristics of transactions, understand the four basic properties of transactions (Atomicity, Consistency, Isolation, Durability), and how to use transactions to manage data operations in the database.
Data Cleaning and Import: Master the importance and methods of data cleaning, and understand how to clean and prepare data to ensure data quality.