EXISTS¶

The exists clause tests for the existence of any rows in a subquery.

Syntax¶

SELECT <column_name> [ ,... ]
FROM <table_name>
WHERE EXISTS (<subquery>)

Arguments¶

Parameter	Description
`column_name`	The columns to retrieve
`table_name`	The table from which to retrieve the data.

Returns¶

Returns TRUE if the subquery returns one or more rows, and FALSE if the subquery returns no rows

Examples¶

SELECT
  employee_id,
  employee_name
FROM
  employees
WHERE
  EXISTS (
    SELECT
      1
    FROM
      departments
    WHERE
      departments.department_id = employees.department_id
  );