diff --git a/Microsoft Access/Sample Databases/SalesOrdersExample.accdb b/Microsoft Access/Sample Databases/SalesOrdersExample.accdb
new file mode 100644
index 0000000..eb3d84e
Binary files /dev/null and b/Microsoft Access/Sample Databases/SalesOrdersExample.accdb differ
diff --git a/Microsoft SQL Server/Chapter 04/Listing 4.018.sql b/Microsoft SQL Server/Chapter 04/Listing 4.018.sql
index 7d5a22b..8e728a1 100644
--- a/Microsoft SQL Server/Chapter 04/Listing 4.018.sql	
+++ b/Microsoft SQL Server/Chapter 04/Listing 4.018.sql	
@@ -17,7 +17,7 @@ GO
 
 -- Sample query that searches products correctly:
 CREATE VIEW ProdsOfInterest AS
-SELECT Products.ProductName,
+SELECT DISTINCT 
        CASE WHEN Products.ProductName LIKE '%Skateboard%' THEN 'Skateboard'
               WHEN Products.ProductName LIKE '%Helmet%' THEN 'Helmet'
               WHEN Products.ProductName LIKE '%Knee Pads%' THEN 'Knee Pads'
diff --git a/Microsoft SQL Server/Chapter 04/Listing 4.019.sql b/Microsoft SQL Server/Chapter 04/Listing 4.019.sql
index 2b8896c..934ab36 100644
--- a/Microsoft SQL Server/Chapter 04/Listing 4.019.sql	
+++ b/Microsoft SQL Server/Chapter 04/Listing 4.019.sql	
@@ -58,7 +58,7 @@ INNER JOIN Products
 GO
 
 CREATE VIEW ProdsOfInterest AS
-SELECT Products.ProductName,
+SELECT DISTINCT 
        CASE WHEN Products.ProductName LIKE '%Skateboard%' THEN 'Skateboard'
               WHEN Products.ProductName LIKE '%Helmet%' THEN 'Helmet'
               WHEN Products.ProductName LIKE '%Knee Pads%' THEN 'Knee Pads'
diff --git a/Microsoft SQL Server/Chapter 04/Listing 4.020.sql b/Microsoft SQL Server/Chapter 04/Listing 4.020.sql
index cfb9b67..e2eff84 100644
--- a/Microsoft SQL Server/Chapter 04/Listing 4.020.sql	
+++ b/Microsoft SQL Server/Chapter 04/Listing 4.020.sql	
@@ -56,7 +56,7 @@ INNER JOIN Products
 GO
 
 CREATE VIEW ProdsOfInterest AS
-SELECT Products.ProductName,
+SELECT DISTINCT 
        CASE WHEN Products.ProductName LIKE '%Skateboard%' THEN 'Skateboard'
               WHEN Products.ProductName LIKE '%Helmet%' THEN 'Helmet'
               WHEN Products.ProductName LIKE '%Knee Pads%' THEN 'Knee Pads'
diff --git a/MySQL/Chapter 04/Listing 4.018.sql b/MySQL/Chapter 04/Listing 4.018.sql
index da69c4f..b4368a5 100644
--- a/MySQL/Chapter 04/Listing 4.018.sql	
+++ b/MySQL/Chapter 04/Listing 4.018.sql	
@@ -15,7 +15,7 @@ DROP VIEW ProdsOfInterest;
 
 -- Sample query that searches products correctly:
 CREATE VIEW ProdsOfInterest AS
-SELECT Products.ProductName,
+SELECT DISTINCT 
        CASE WHEN Products.ProductName LIKE '%Skateboard%' THEN 'Skateboard'
               WHEN Products.ProductName LIKE '%Helmet%' THEN 'Helmet'
               WHEN Products.ProductName LIKE '%Knee Pads%' THEN 'Knee Pads'
diff --git a/MySQL/Chapter 04/Listing 4.019.sql b/MySQL/Chapter 04/Listing 4.019.sql
index 0d85df5..3127a1e 100644
--- a/MySQL/Chapter 04/Listing 4.019.sql	
+++ b/MySQL/Chapter 04/Listing 4.019.sql	
@@ -50,7 +50,7 @@ INNER JOIN Products
   ON Products.ProductNumber = Order_Details.ProductNumber;
 
 CREATE VIEW ProdsOfInterest AS
-SELECT Products.ProductName,
+SELECT DISTINCT 
        CASE WHEN Products.ProductName LIKE '%Skateboard%' THEN 'Skateboard'
               WHEN Products.ProductName LIKE '%Helmet%' THEN 'Helmet'
               WHEN Products.ProductName LIKE '%Knee Pads%' THEN 'Knee Pads'
diff --git a/MySQL/Chapter 04/Listing 4.020.sql b/MySQL/Chapter 04/Listing 4.020.sql
index e58a2f4..09acccf 100644
--- a/MySQL/Chapter 04/Listing 4.020.sql	
+++ b/MySQL/Chapter 04/Listing 4.020.sql	
@@ -48,7 +48,7 @@ INNER JOIN Products
   ON Products.ProductNumber = Order_Details.ProductNumber;
 
 CREATE VIEW ProdsOfInterest AS
-SELECT Products.ProductName,
+SELECT DISTINCT 
        CASE WHEN Products.ProductName LIKE '%Skateboard%' THEN 'Skateboard'
               WHEN Products.ProductName LIKE '%Helmet%' THEN 'Helmet'
               WHEN Products.ProductName LIKE '%Knee Pads%' THEN 'Knee Pads'