I am working on a web app. I have a question about the SQL parts. I am currently creating a food rating interface. The user should be able to login and then rate the food. Currently I use a custom database (users) for the login page. I also use a separate database (review) for the reviews. my current database structure
Tag: entity-relationship
How to transform complex form/poll questions to SQL tables?
I need to make system design out of some big form/poll and transform all of that in SQL tables and make db out of it. My problem are questions in which user can choose answer or if the answer is not preset to write it down. So for example question is: Where did you bought your groceries? 1 – walmart
How to make Custom attributes for SQL table
What is the proper way to give user to use custom attributes ? As an example Consider that, There is a web application, using the frontend user interface admin user need to be able to add custom …
Is It Possible to Derive an Attribute from other Tables Attribute
Is it possible to derive the attribute “total cost” from “Total Cash Purchases” and “Total Salary Paid”. Im also open for suggestion if there are any problems in my …
How to remove redundancy when a lot of columns can have repeating data?
I am working on a library system. I have a book table in which there are 12 columns including author, title, publication etc. Among those 12 there are 2 columns book_id and isbn that are unique. When a library get n copies of a same book the only columns that are going to be unique are book_id and isbn. All
how to setup this diagram? (multiple selling methods)
I’m supposed to create a sort of second brand website. When someone wants to sell a product, he has the option to sell it for: a set amount free to bid can anyone give me an assist on how to continue? This is what i have so far, but i’m stuck and don’t know how to continue. (sorry for the
Two composite foreign keys with one column in common
I am trying to map the following ER Model into PostgreSQL and I am having trouble with the Issue_Label table. It requires the key from the Issue table, which is id and the key from the Label table, …
Toad Notation – What do (Ix#)’s mean?
So, I’m trying to visualize a database, and I have some tables put together which consist of a mix of object-oriented and relational; just trying to tie them together. My issue is, I can’t seem to …
how to show partial key in uml er diagram
in chen’s notation partial keys (discriminator) were shown as dashed lines, how are they shown in uml er (entity-relationship) diagram?