Which command is used to implement data query in sql

In SQL, the command used for data query is SELECT, and the syntax is SELECT [column1, column2, ...] FROM table_name [WHERE condition] [ORDER BY ...] [LIMIT ...] , used to select specific columns, filter results, sort, and limit the number of rows.

Commands used to implement data query in SQL

In SQL, the commands used to implement data query areSELECT.

Syntax:

SELECT [column1, column2, ...] FROM table_name [WHERE condition] [ORDER BY ...] [LIMIT ...]

Parameters:

• ##column1, column2, ...: Column to select.
• table_name: The name of the table to be queried.
• WHERE condition: Optional condition used to filter results.
• ORDER BY: Used to sort the results by the specified column.
• LIMIT: Used to limit the number of rows in query results.

Example:

SELECT * FROM employees;

SELECT first_name, salary FROM employees ORDER BY salary DESC;

SELECT * FROM employees WHERE age > 30;

SELECT * FROM employees LIMIT 10;

Note:

The SELECT command is one of the most important commands in SQL and is used to retrieve and manipulate data.
• The column names in the query conditions must be valid columns in the table.
• The query result is a temporary table that can only be used in this session.

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