What are relational databases?

Relational database is a database based on the relational model, which uses mathematical concepts and methods such as set algebra to process data in the database. Various entities in the real world and various connections between entities are represented by relational models. The standard data query language SQL is a language based on relational databases. This language performs retrieval and operation of data in relational databases.

Common relational databases include mysql, SQL Server, Oracle, Sybase, DB2, etc. Relational database is currently the most popular database management system, and the technology is relatively mature.

MySQL

MySQL is currently the most popular open source SQL database management system. Compared with other large databases such as Oracle, DB2, SQL Server, etc. Although MySQL has its shortcomings, it has not reduced its popularity at all. For individuals or small and medium-sized enterprises, the functions of MySQL are sufficient. MySQL is open source software, so there is no need to spend a lot of effort and money to use a large paid database management system.

Features:

1. MySQL is open source and free.

2. MySQL server is reliable, easy to use, and fast.

3. MySQL server works in a client/server or embedded system.

4. There are many MySQL software.

5. MySQL is a relational database management system.

SQL Server

SQL Server is a relational database management system developed by Microsoft and is generally used to store data on the Web. SQL Server provides many functions, such as rich support for XML and Internet standards, easy and secure access to data through the Web, flexible, secure, and Web-based application management, and an easy-to-operate operation interface. Loved by the majority of users.

Oracle

Oracle has always been in a leading position in the database field. Due to the continuous updating of advanced technology, Oracle products currently cover a wide range of products and have become the most widely used in the world. One of the relational data systems.

Complete data management functions:

1. Large amount of data

2. Durability of data storage

4. Sharing of data

5. Data reliability

Sybase

Sybase A relational database system developed by the American Sybase Company, which is a typical UNIX Or a large database system in a client/server environment on the Windows NT platform.

Features:

1. Client/server architecture

2. Truly open

3. High performance

DB2

DB2 is a relational database management system developed by IBM in the United States. It is mainly used in large-scale application systems and has good scalability.

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