I'm trying to create an ERD for a supermarket chain and I got stuck after creating the products and store table. under products I have ProdID as the primary key and under store I have storeID as the primary key. My problem is how would I differentiate the different products at each store? If I added an inventory table what would be the primary key for that?
![[H]ard|Forum](/styles/hardforum/xenforo/logo_dark.png){kind=logo}
Navigation
Install the app
How to install the app on iOS
Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
More options
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an alternative browser.
You should upgrade or use an alternative browser.
chain supermarket inventory ERD
- Thread starter syn3rgyz
- Start date
Wiseguy2001
2[H]4U
- Joined
- Nov 28, 2001
- Messages
- 3,470
You need another table to link the other two tables together, also you may want to include some additional attributes in the column such as price (I guarantee there will be variations from store to store) and stock level.
Plus there is the multiple levels/ type of discounts - have fun!
Plus there is the multiple levels/ type of discounts - have fun!
Wiseguy2001
2[H]4U
- Joined
- Nov 28, 2001
- Messages
- 3,470
Then you have solved it already.
No it isn't a problem as long as you have unique indexes in a given table. This can be by using a surrogate key (unique but doesn't really mean anything) or use compound keys which are a combination of other (typically foreign) keys.
No it isn't a problem as long as you have unique indexes in a given table. This can be by using a surrogate key (unique but doesn't really mean anything) or use compound keys which are a combination of other (typically foreign) keys.