You can include SQL statements within stored functions , although you should be very careful about including SQL statements in a stored function that might itself be used inside a SQL statement (more on that later).
However, you cannot return a result set from a stored function:
trying to create a stored function that contains a
SELECT statement without an
INTO clause will result in a 1415 error, as
shown in Example
Example 10-5. Stored functions cannot return result sets
mysql> CREATE FUNCTION test_func( ) -> RETURNS INT -> BEGIN -> SELECT 'Hello World'; -> RETURN 1; -> END;$$ ERROR 1415 (0A000): Not allowed to return a result set from a function