函数

CREATE OR REPLACE FUNCTION chk_null (pinput NUMBER)
RETURN CHAR
IS
BEGIN
IF pinput IS NULL
THEN
RETURN ‘Y’;
ELSE
RETURN ‘N’;
END IF;
END;

----函数不能重载 ；但是再packages包里是可以的
–CREATE OR REPLACE FUNCTION chk_null (pinput VARCHAR2)
– RETURN CHAR
– IS
– BEGIN
– IF pinput IS NULL
– THEN
– RETURN ‘Y’;
– ELSE
– RETURN ‘N’;
– END IF;
– END;