All Questions
Tagged with database-design object-oriented-design
25
questions
1
vote
1
answer
329
views
Representing database tables as objects
I'm building an address book API, where a user can input multiple contact names, phone numbers, and addresses.
My database structure would be as follows:
create table user (
id int not null primary ...
- 19
-4
votes
1
answer
97
views
Name of design pattern where type and instance classes are mirrored
I have used this design pattern in several entity-component designs. Now I want to introduce it to my team:
It concerns a type-of relationship, where the instance structure and the type structure are ...
- 93
3
votes
0
answers
55
views
How Best To Store Data Structures Around Flow
I'm working on building a simulator for HVAC units. The conceptual model I am working with is basically that an HVAC unit has inputs and outputs, and I need to be able to calculate the outputs for a ...
- 570
0
votes
1
answer
926
views
Is it good practice to create a static class for database tables calculations?
I need to implement some system (using python pandas dataframe in my case) that parses raw data, then adds on calculated data, and then validates that calculated data (boolean output on some columns)
...
- 1,240
2
votes
2
answers
141
views
Is ER model used in database design and software design the same thing?
ER model appears in both database design and software design.
I was wondering if ER models in both designs are the same concept? If not, what are their differences?
Thanks.
- 5,485
1
vote
1
answer
139
views
What is the solution of enum based dynamic states and actions used in a project
I have recently started working on a project where we have a workflow engine which has flexibility to add dynamic states and corresponding actions for each state and all these are stored in database.
...
- 111
1
vote
2
answers
280
views
Save not-so dynamic data into a database and retrieve with changes in the future
Imagine this use case:
I have a class with 50 attributes of which 10 are relationships plus 100 methods which perform calculations and return a value.
I need to save that data (including ...
- 113
0
votes
1
answer
97
views
Design tables and models for shipment and changes and keep it normalized
Our company buys second hand valuables (item) from clients and resell them for them. In order to do the client comes to our site and ask for a shipment he may choose the time that the delivery man ...
- 131
-1
votes
2
answers
242
views
Hierarchy in ER and OO Model
So, it might be a very fundamental question, but I'm pretty confusing right now...
It's all about Element and ElementCategory: an element belongs to a category, a categoty can have many elements - a ...
- 55
-3
votes
1
answer
124
views
What are steps to follow in order to create an application (web/mobile)? [closed]
I have an application that manage absence of students.
I asked everyone who will use the application (teachers , administration ...) about their needs and feature they want to see in the application....
- 135
1
vote
1
answer
4k
views
Class Design for JPA Entities with Multiple Tables Referring to Same Business Object
I have an application that works with products from various external data sources (in DataSourceProduct) and it also maintains its own version of the product (in MasterProduct). Here's the DB schema:
...
- 285
1
vote
1
answer
758
views
Doubt about representing a Shopping Cart in Class Diagram/ER Database implicating ORM
I have to do a task which is reading a text, and create a Class diagram. One of the entities is a Shopping Cart.
My doubt is how to represent a Shopping Cart in a class diagram, later on an E/R ...
- 19
0
votes
2
answers
66
views
Filtering Deleted Objects
Picture a simple messaging app written in Django.
Users have the option to delete messages at any time, but the messages need to be retained in the database. There are two options:
A deleted ...
- 103
3
votes
4
answers
254
views
Hierarchical structure that needs to enforce availability
The project I am working on has deep parent/child relationships that needs to enforce availability.
Imagine we are a large Worldwide Electronic Seller (Best Buy) and selling mobile phones
We have ...
- 131
4
votes
2
answers
158
views
Proper design for models
I have a class called ReplaceRule this is used by 2 classes DocumentRuleViewModel and SectionRuleViewModel as a List<ReplaceRule> in both
Question 1:
In my database implementation I have 2 ...
- 178