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This article mainly introduces the relevant knowledge of SQL grammar, the content is detailed and easy to understand, the operation is simple and fast, and it has a certain reference value. I believe you will gain something after reading this SQL grammar article. Let's take a look at it.

The structured query language (SQL) consists of six parts, namely:

Data query language (SELECT statement, WHERE,GROUP BY, etc.)

Data manipulation language (INSERT,UPDATE,DELETE three action statements)

Transaction processing language (statements for transaction processing, such as ROLLBACK,COMMIT)

Data control language (GRANT,REVOKE and other statements for user rights management)

Data definition language (statements such as CREATE,DROP that create or delete tables that define data structures)

Pointer control language (statements such as DECLARE CURSOR,FETCH INTO that operate alone on the form).

Using the data plane

For ordinary back-end programmers, the database is only used to access data, and the data tables are designed by database engineers, so for back-end programmers, it is enough to master the four operations of data Create, Retrieve, Update and Delete. These four operations correspond to INSERT statement, SELECT statement, UPDATE statement and DELETE statement respectively. Therefore, these four statements must be fully mastered by back-end developers.

Data structure level

If you are a database engineer, you also need to know how to create and delete data tables, how to establish relationships between tables, how to build indexes, and how to design databases, so you need to be proficient in all six parts mentioned above, and you need to learn the introduction to database systems (for database systems engineering, SQL is a tool for designing databases, so you must firmly grasp it). For database engineers, pointer control language, data definition language, data control language and transaction language are more often used.

This is the end of the article on "what are the grammars of SQL?" Thank you for reading! I believe you all have a certain understanding of "what is the grammar of SQL". If you want to learn more, you are welcome to follow the industry information channel.

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