Changes between Version 19 and Version 20 of Conceptual Design – ER Diagram and Data Requirements

Timestamp:

08/28/25 21:54:11 (5 days ago)

Author:

221531

Comment:

--

Conceptual Design – ER Diagram and Data Requirements

@@ -140 +140 @@
 * item_id - foreign key, required
 
+**24. Shopping Cart**\\
+* cart_id - primary key, numeric, required
+
+**25. Cart Items**\\
+* cart_id - foreign key, required
+* item_id - foreign key, required
+* quantity - numeric type, required
+
+
 === Relations===
 === 1:1 ===
@@ -150 +159 @@
 * Admin → App User  \\
     **''manages''** – a relation which indicates that an admin is responsible for management of many users and a user is managed by a single admin.
+
+* Customer → Shopping Cart  \\
+    **''has''** – a relation which indicates that a customer has 1 shopping cart, and a shopping cart belongs to a user.
+
 === 1:M ===
 
@@ -216 +229 @@
     **''contains''** – relation between Menu and Item where an item can belong to many menu's and a menu can have many items.\\
 
+\\
+* Shopping Cart ↔ Shopping Cart Items ↔ Item\\
+    **Junction: ** Shopping Cart Items solves M:N relation of Shopping Cart and Item, by storing the composite key (cart_id, item_id)\\
+
+    **''cart_items''** – relation between Shopping Cart and Item where an item can belong to many shopping cart's and a shopping cart can have many items.\\