What are the core statements of SQL?

The core statement of SQL language is: SELECT statement, which is used to select data from the table. The full name of SQL is Structured Query Language (Structured Query Language), its core is data query, and its query language has only one, namely SELECT statement.

The operating environment of this tutorial: Windows 7 system, mysql version 5.8, Dell G3 computer.

The core statement of SQL language is: data query SELECT statement, which is used to select data from the table.

The data in the database is often for query, so data query is the core operation of the database. In SQL, there is only one query language, which is the SELECT statement.

The SELECT statement can be used to query and select data; the results are stored in a result table, called a result set. Querying data refers to using different query methods to obtain different data from the database according to needs. It is the most frequently used and important operation.

SQL SELECT syntax

SELECT column_name,column_name
FROM table_name;

and

SELECT * FROM table_name;

Extended information:

Structured Query Language (Structured Query Language) referred to as SQL , a special-purpose programming language, is a database query and programming language used to access data and query, update, and manage relational database systems.

Functions of SQL language:

SQL has the functions of data definition, data manipulation and data control.

1. SQL data definition function: Able to define the three-level schema structure of the database, namely external schema, global schema and internal schema structure. In SQL, the external schema is also called View, and the global schema is referred to as Schema. The internal schema is automatically implemented by the system based on the database schema, and generally does not require user intervention.

2. SQL data manipulation functions: including data insertion, deletion and modification of basic tables and views, especially strong data query functions.

3. SQL data control function: mainly controls user access rights to ensure system security.

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