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2025-01-18 Update From: SLTechnology News&Howtos shulou NAV: SLTechnology News&Howtos > Database >
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This article mainly introduces what the main features of SQL language include, the article is very detailed, has a certain reference value, interested friends must read it!
The SQL language is the standard language for "relational databases". SQL is a special purpose programming language, which is a database query and programming language, which is used to access data and query, update and manage relational database systems.
The SQL language is the standard language for "relational databases".
The SQL language was proposed by Boyce and Chamberlin in 1974 and was first implemented on the relational database system SystemR developed by IBM Company. Because of its outstanding advantages such as rich functions, convenient and flexible use, concise and easy to learn language, it is deeply welcomed by the computer industry and computer users. In October 1980, X3H2, the database committee of the American National Standards Institute (ANSI), approved SQL as the American standard for relational database language, and published the standard SQL in the same year. Shortly after that, the International Organization for Standardization (ISO) made the same decision.
SQL language integrates the functions of data query, data manipulation (DML), data definition (DDL) and data control (DCL), which fully embodies the characteristics and advantages of relational database language. Its main features include:
Comprehensive unity. SQL language integrates the functions of data definition language (DDL), data manipulation language (DML) and data control language (DCL), and has a unified language style.
Non-procedural. To manipulate data in SQL, users only need to suggest "what to do" instead of "how to do it".
Collection-oriented operation. SQL language adopts the mode of set operation, not only the search result can be a collection of tuples, but also the objects of insert, delete and update operation can also be a collection of tuples (one collection at a time).
Provide two ways of use in the same grammatical structure. SQL is both a self-contained language and an embedded language. As a self-contained language, it can be used independently for the use of online interaction, and users can directly input SQL commands on the terminal keyboard to operate the database. As an embedded language, SQL statements can be embedded in programs in high-level languages (such as C, COBOL, FORTRAN).
The language is concise and easy to learn and use.
The above is all the contents of the article "what are the main features of SQL language?" Thank you for reading! Hope to share the content to help you, more related knowledge, welcome to follow the industry information channel!
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