ongoing work on lab 8 script

lab-8/music-store-app/views/place-order.php

@@ -14,9 +14,13 @@ mysqli_query($link, 'START TRANSACTION');
 
 // fetch the albums so that we have access to their names and upc's
 // lock in shared mode so affected data cannot be altered by other 
-// sessions BEFORE the transaction is committed or rolled back
+// sessions BEFORE the transaction is committed or rolled back.
+// only list albums that are in stock.
 $sql = "SELECT title, upc
         FROM Album
+		INNER JOIN Inventory
+		ON Album.upc=Inventory.album_upc
+		WHERE Inventory.stock>0
 	    ORDER BY title LOCK IN SHARE MODE";
 
 $result = mysqli_query($link, $sql);