oracle定義變量以及變量的使用

DECLARE
	xiaoyi VARCHAR2 (50) ;
BEGIN
	xiaoyi := 'xiaoyiid' ; 
	FOR item IN (
		SELECT
			*
		FROM
			USER u
		WHERE
			u.id = xiaoyi
	) LOOP
 
	 dbms_output.put_line (u.id) ;
 
	END LOOP ;
END ;