What is SQL's advanced and oriented operating language?

SQL is a highly non-procedural and set-oriented operating language. When using SQL to perform data operations, users only need to ask "what to do" instead of specifying "how to do it". Therefore, users do not need to know the access path. The selection of the access path and the operation process of the SQL statement are automatically completed by the system; SQL uses sets Operation method.

sql (Structured Query Language) is a special purpose programming language, a database query and programming language, used for Access data and query, update, and manage relational database systems.

SQL language is a high-level non-procedural programming language that allows users to work on high-level data structures. It does not require users to specify the data storage method, nor does it require users to understand the specific data storage method, so different database systems with completely different underlying structures can use the same structured query language as the interface for data input and management. SQL language statements can be nested, which makes it extremely flexible and powerful.

Characteristics of SQL language:

• ##Uniform SQL style

  SQL can independently complete all activities in the database life cycle, including defining relational schemas, entering data, establishing databases, querying, updating, maintaining, database reconstruction, database security control and a series of operations. This provides the basis for the development of database application systems. It provides a good environment. After the database is put into operation, the mode can be gradually modified at any time as needed without affecting the operation of the database, thus making the system highly scalable.

• Highly non-procedural

  The data manipulation language of the non-relational data model is a process-oriented language. When completing a user request, an access path must be specified. When using SQL to perform data operations, the user only needs to ask "what to do" instead of "how to do it". Therefore, the user does not need to know the access path. The selection of the access path and the operation process of the SQL statement are automatically completed by the system. This not only greatly reduces the burden on users, but also helps improve data independence.

• Set-oriented operation mode

  SQL adopts a set operation mode, not only the search result can be a collection of tuples , and the object of an insertion, deletion, and update operation can also be a collection of tuples.

• Provides two usage methods with the same syntax structure

  SQL is both a self-contained language and an embedded language. As a self-contained language, it can be used independently for online interaction. Users can directly enter SQL commands on the terminal keyboard to operate the database. As an embedded language, SQL statements can be embedded into high-level language (such as C, C#, JAVA) programs for programmers to use when designing programs. Under two different usage methods, the syntax structure of SQL is basically the same. This provides two different operation modes with a unified syntax structure, providing users with great flexibility and convenience.

• The language is concise, easy to learn and use

  SQL is extremely powerful, but due to its clever design, the language is very concise and completes data definition and data manipulation. , The core functions of data control only use 9 verbs: CREATE, ALTER, DROP, SELECT, INSERT, UPDATE, DELETE, GRANT, REVOKE. Moreover, the syntax of SQL language is simple and close to spoken English, so it is easy to learn and use.

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