CREATE OR REPLACE FUNCTION wordcount (str IN VARCHAR2)
   RETURN PLS_INTEGER
AS
   words PLS_INTEGER := 0;  
   len PLS_INTEGER := NVL(LENGTH(str),0);
   inside_a_word BOOLEAN;
BEGIN
   FOR i IN 1..len + 1
   LOOP
      IF ASCII(SUBSTR(str, i, 1)) < 33 OR i > len
      THEN
         IF inside_a_word
         THEN
            words := words + 1;
            inside_a_word := FALSE;
         END IF;
      ELSE
         inside_a_word := TRUE;
      END IF;
   END LOOP;
   RETURN words;
END;
/