Polish your eyes to see the historical origins of SQL Server (1)

In the second article in the SQL Server series, I have mentioned that I want to write historical data. The history here mainly describes the historical data of the database and the SQL Server itself. To be honest, this part of content should be clear, and the personal feeling is more difficult and abstract. My personal abilities are limited. If there is anything inappropriate or wrong in this article, I hope you can point it out. It can be said that the birth and development of databases has brought about a huge revolution in computer information management, over the past 40 years, the database field has won three computer Turing Awards, which fully demonstrates that the database field is a dynamic and innovative field.

Just like studying any technology, you can understand the following questions to understand the technology: 1. What problems does database technology mainly solve? 2. Understanding the development of database technology? 3. What stages does database technology go through. Let's talk about these issues one by one.

I. What problems does database technology mainly solve?

Databases are computer-based. Computers have now penetrated into any corner of our lives. However, computers mainly solve two problems: computing and data processing. The computer was born in 1940s and was originally used only for scientific computing and cannot be used for data processing. At that time, the computer could only process numbers, but not letters and symbols. letters and symbols were the main processing objects in data processing. At that time, there was indeed no large-capacity storage required for data processing. To address these two problems, a character generator emerged in 1950s and the high-speed tape drive was successfully used for computer storage. Solving these two problems plays a decisive role for computers to process data. Later, IBM Remington Rand successfully launched the disk system because the tape drive was not fast enough. These hardware drives the development of computer data processing.

From the above, we can see that database technology is a data processing technology. A similar solution is file management. Many people have such doubts that files can be processed completely. Why is database technology required? In file management, data files correspond to applications one by one, resulting in data redundancy, data inconsistency, and data dependency. This poses a lot of problems for programming data maintenance. Later, the file management system emerged as an interface between applications and data files. These applications only need to interact with the file management system to bring some flexibility. However, this method still solves the problems of non-data redundancy, Database Consistency, and low processing efficiency, especially in Large-Scale Systems. In response to these problems, people subsequently made a lot of explorations to solve the disadvantages of the scattered management of the file management system, and introduced the database technology, which can centrally control and manage data. The following figure shows the differences between the three methods described here.

To sum up, the database technology at that time mainly solved the problems of data redundancy, data inconsistency, low processing efficiency, and scattered management in the file management system during data processing. With the development of database technology, more problems will be solved.