What does from mean in mysql?

FROM is a keyword in a MySQL query that is used to specify the data source (table or view). It is used in a SELECT statement to identify the data participating in the query and ensure that the data returned is relevant to the specified data source.

FROM in MySQL

In MySQL queries, the FROM keyword is used to specify the data source, that is, to The table or view from which data is retrieved. It follows the SELECT statement and is used to identify the data participating in the query operation.

Function:

The FROM keyword tells MySQL which table or view to get data from. It ensures that the query returns only data relevant to the specified data source.

Syntax:

<code>SELECT ...
FROM table_name [AS alias]
[JOIN ...]
[WHERE ...]</code>

Where:

• table_name is the name of the table or view from which data is to be retrieved .
• AS alias (Optional) Specify an alias for the table or view to make it easier to reference it in queries.
• JOIN (optional) is used to join multiple tables or views to combine data.
• WHERE (optional) is used to add filter conditions to limit the returned rows.

Example:

<code>SELECT *
FROM employees
WHERE salary > 50000;</code>

This query selects all rows from the table named employees, conditional on salary The value of the column is greater than 50,000.

Note:

• The FROM keyword is a required part of the SELECT statement. If the data source is not specified, the query will return an error.
• Multiple data sources can be specified (using JOIN), but each data source must have a unique alias.
• Aliases are useful for making queries more readable and maintainable.

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