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Editor to share with you what the common features of sql language are, I believe most people do not know much about it, so share this article for your reference, I hope you can learn a lot after reading this article, let's go to know it!

Sql language has three common functions: 1. Data definition; it can define the three-level schema structure of the database, namely, external schema, global schema and internal schema structure. 2. Data manipulation, including data insertion, deletion, modification and query for basic tables and views. 3. Data control, mainly to control the access rights of users to ensure the security of the system.

Sql language is a structured query language, which can store data, update and query database. Sql language has the characteristics of unified style, high degree of non-process, easy to learn and use.

Sql language has three common functions: data definition, data operation and data control.

1. Data definition function of SQL

Can define the three-level schema structure of the database, namely, external schema, global schema and internal schema structure. In SQL, the outer schema is called View, and the global schema is called Schema. The inner schema is automatically implemented by the system according to the database schema, and generally does not need to be asked by the user.

2. Data manipulation function of SQL

It includes data insertion, deletion and modification of basic tables and views, especially with strong data query function.

3. Data control function of SQL.

The main purpose is to control the access rights of users in order to ensure the security of the system.

These are all the contents of this article entitled "what are the common functions of the sql language?" Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!

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