diff --git a/IBM DB2/Chapter 01/Listing 1.001.sql b/IBM DB2/Chapter 01/Listing 1.001.sql
index 1318791..d5aea89 100644
--- a/IBM DB2/Chapter 01/Listing 1.001.sql	
+++ b/IBM DB2/Chapter 01/Listing 1.001.sql	
@@ -3,9 +3,12 @@
 
 SET SCHEMA Item02Example;
 
-SELECT ST.SalesID, C.CustFirstName, C.CustLastName, C.Address, C.City, C.Phone, 
-       ST.PurchaseDate, M.ModelYear, M.Model, E.SalesPerson
-  FROM SalesTransactions ST, Employees E, Customers C, AutomobileModels M
- WHERE C.CustomerID = ST.CustomerID
-   AND M.ModelID = ST.ModelID
-   AND E.EmployeeID = ST.SalesPersonID;
+SELECT st.SalesID, c.CustFirstName, c.CustLastName, c.Address, c.City, c.Phone,
+  st.PurchaseDate, m.ModelYear, m.Model, e.SalesPerson
+FROM SalesTransactions AS st
+  INNER JOIN Customers AS c
+    ON c.CustomerID = st.CustomerID
+  INNER JOIN Employees AS e
+    ON e.EmployeeID = st.SalesPersonID
+  INNER JOIN AutomobileModels AS m
+    ON m.ModelID = st.ModelID;
\ No newline at end of file
diff --git a/Microsoft SQL Server/Chapter 01/Listing 1.001.sql b/Microsoft SQL Server/Chapter 01/Listing 1.001.sql
index 847f8b9..49ef3e8 100644
--- a/Microsoft SQL Server/Chapter 01/Listing 1.001.sql	
+++ b/Microsoft SQL Server/Chapter 01/Listing 1.001.sql	
@@ -4,9 +4,12 @@
 USE Item02Example;
 GO
 
-SELECT ST.SalesID, C.CustFirstName, C.CustLastName, C.Address, C.City, C.Phone, 
-       ST.PurchaseDate, M.ModelYear, M.Model, E.SalesPerson
-  FROM SalesTransactions ST, Employees E, Customers C, AutomobileModels M
- WHERE C.CustomerID = ST.CustomerID
-   AND M.ModelID = ST.ModelID
-   AND E.EmployeeID = ST.SalesPersonID;
+SELECT st.SalesID, c.CustFirstName, c.CustLastName, c.Address, c.City, c.Phone,
+  st.PurchaseDate, m.ModelYear, m.Model, e.SalesPerson
+FROM SalesTransactions st
+  INNER JOIN Customers c
+    ON c.CustomerID = st.CustomerID
+  INNER JOIN Employees e
+    ON e.EmployeeID = st.SalesPersonID
+  INNER JOIN AutomobileModels m
+    ON m.ModelID = st.ModelID;
diff --git a/Oracle/Chapter 01/Listing 1.001.sql b/Oracle/Chapter 01/Listing 1.001.sql
index df56ee2..d0513d9 100644
--- a/Oracle/Chapter 01/Listing 1.001.sql	
+++ b/Oracle/Chapter 01/Listing 1.001.sql	
@@ -3,9 +3,13 @@
 
 ALTER SESSION SET CURRENT_SCHEMA = Item02Example;
 
-SELECT ST.SalesID, C.CustFirstName, C.CustLastName, C.Address, C.City, C.Phone, 
-       ST.PurchaseDate, M.ModelYear, M.Model, E.SalesPerson
-  FROM SalesTransactions ST, Employees E, Customers C, AutomobileModels M
- WHERE C.CustomerID = ST.CustomerID
-   AND M.ModelID = ST.ModelID
-   AND E.EmployeeID = ST.SalesPersonID;
+SELECT st.SalesID, c.CustFirstName, c.CustLastName, c.Address, c.City, c.Phone,
+  st.PurchaseDate, m.ModelYear, m.Model, e.SalesPerson
+FROM SalesTransactions st
+  INNER JOIN Customers c
+    ON c.CustomerID = st.CustomerID
+  INNER JOIN Employees e
+    ON e.EmployeeID = st.SalesPersonID
+  INNER JOIN AutomobileModels m
+    ON m.ModelID = st.ModelID;
+
diff --git a/PostgreSQL/Chapter 01/Listing 1.001.sql b/PostgreSQL/Chapter 01/Listing 1.001.sql
index 059878e..5b0c82b 100644
--- a/PostgreSQL/Chapter 01/Listing 1.001.sql	
+++ b/PostgreSQL/Chapter 01/Listing 1.001.sql	
@@ -3,9 +3,13 @@
 
 SET search_path = Item02Example;
 
-SELECT ST.SalesID, C.CustFirstName, C.CustLastName, C.Address, C.City, C.Phone, 
-       ST.PurchaseDate, M.ModelYear, M.Model, E.SalesPerson
-  FROM SalesTransactions AS ST, Employees AS E, Customers AS C, AutomobileModels AS M
- WHERE C.CustomerID = ST.CustomerID
-   AND M.ModelID = ST.ModelID
-   AND E.EmployeeID = ST.SalesPersonID;
\ No newline at end of file
+SELECT st.SalesID, c.CustFirstName, c.CustLastName, c.Address, 
+  c.City, c.Phone, st.PurchaseDate, m.ModelYear, m.Model, 
+  e.SalesPerson
+FROM SalesTransactions AS st
+  INNER JOIN Customers AS c
+    ON c.CustomerID = st.CustomerID
+  INNER JOIN Employees AS e
+    ON e.EmployeeID = st.SalesPersonID
+  INNER JOIN AutomobileModels AS m
+    ON m.ModelID = st.ModelID;
\ No newline at end of file