diff --git a/6_join.sql b/6_join.sql
index 0ea19af..a2f7617 100644
--- a/6_join.sql
+++ b/6_join.sql
@@ -104,7 +104,7 @@ SELECT game.mdate,
            ELSE 0
            END) AS score2
 FROM game
-JOIN goal
+LEFT JOIN goal
 ON (game.id = goal.matchid)
 GROUP BY game.id
-ORDER BY game.mdate, goal.matchid
\ No newline at end of file
+ORDER BY game.mdate, goal.matchid
diff --git a/7_more_join_operations.sql b/7_more_join_operations.sql
index 15d5953..6440b88 100644
--- a/7_more_join_operations.sql
+++ b/7_more_join_operations.sql
@@ -121,13 +121,22 @@ GROUP BY actor.name
 HAVING COUNT(*) >= 30;
 
 -- # 15. List the 1978 films by order of cast list size.
-SELECT movie.title, COUNT(*)
+SELECT movie.title, COUNT(*) 
 FROM movie
 JOIN casting
 ON movie.id = casting.movieid
 WHERE movie.yr = 1978
 GROUP BY movie.id
 ORDER BY COUNT(*) DESC
+-- # Above code gets wrong in MySQL. We have to do some 
+-- # modifictation with it. 
+-- SELECT movie.title, COUNT(*) As actors
+-- FROM movie
+-- JOIN casting
+-- ON movie.id = casting.movieid
+-- WHERE movie.yr = 1978
+-- GROUP BY movie.id
+-- ORDER BY actors DESC
 
 -- # 16. List all the people who have worked with 'Art Garfunkel'.
 SELECT a.name
@@ -143,4 +152,15 @@ SELECT a.name
           JOIN casting
             ON casting.actorid = actor.id
          WHERE actor.name != 'Art Garfunkel') as a
-    ON m.id = a.movieid;
\ No newline at end of file
+    ON m.id = a.movieid;
+-- # Another solution.
+SELECT actor.name 
+FROM actor 
+JOIN casting
+ON actor.id = casting.actorid
+WHERE casting.movieid in (SELECT casting.movieid 
+                            FROM actor
+                            JOIN casting
+                            ON actor.id = casting.actorid
+                            WHERE actor.name='Art Garfunkel')
+AND actor.name != 'Art Garfunkel';