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What is the statement to query data in mysql

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The statement to query data in MySQL is the SELECT statement, which is used to retrieve specified row and column data from the table. The syntax is: SELECT column_list FROM table_name [WHERE condition] [GROUP BY group_by_column] [HAVING condition] [ORDER BY order_by_column]. The SELECT * query retrieves all columns in the table, while the SELECT column_list retrieves specified columns. You can use the WHERE clause to filter the results, and use the GROUP B

What is the statement to query data in mysql

MySQL statement to query data

MySQL to query data. The statement is a SELECT statement. It is used to retrieve specified row and column data from a database table.

Syntax

<code>SELECT column_list
FROM table_name
[WHERE condition]
[GROUP BY group_by_column]
[HAVING condition]
[ORDER BY order_by_column]</code>

Elements

  • column_list: The name of the column to retrieve or expression.
  • table_name: The name of the table to be queried.
  • WHERE condition: Conditions used to filter query results.
  • GROUP BY group_by_column: Used to group the result set by the specified column.
  • HAVING condition: Used to further filter the grouped result set.
  • ORDER BY order_by_column: Used to sort the result set by the specified column.

Example

<code class="sql">SELECT name, email
FROM users;</code>

This query retrieves name and email## from the users table # all rows of column.

<code class="sql">SELECT name, email
FROM users
WHERE age > 18;</code>
This query retrieves all rows from the

users table for which age is greater than 18.

Other Notes

  • SELECT * The query retrieves all columns in the table.
  • You can use aliases to rename columns, for example
  • SELECT name AS username.
  • You can use aggregate functions (such as
  • SUM(), COUNT(), AVG()) to calculate the results.
  • You can also use the JOIN statement to join multiple tables.

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