Questions tagged [relationships]
The relationships tag has no usage guidance.
1
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0answers
41 views
ER diagram - feasibility of a requirement
I need to model the following requirement in an Entity-Relationship diagram.
"Customers place orders, which contain a list of products with their quantity and prices. A shipment is made when ...
1
vote
3answers
93 views
Database relation design
When I develop apps I reach situations like this frequently but I never found a best practice to solve it.
Imagine:
We have chats, each chat can have many message.
We have tickets, each ticket can ...
2
votes
1answer
70 views
Proper way to associate data to users that are stored in external database?
I have this IdentityServer which handles authentication and authorization. It saves users, roles, claims, etc in its own database.
Then, I have a web app that needs to protect some resources to ...
3
votes
3answers
192 views
Factory pattern or builder pattern ? which one is suited for reading Finite Element Model data from a text file?
A follow up to another question (Making a design decision about reading model data from an input file).
I wish to ask another question regarding builder or factory pattern. (I read that builder is ...
1
vote
1answer
297 views
Entities and polymorphic relationships
Lets say that I have a shelf on which I can put items that are shelfable (not sure if that is actually a word but you can understand my point).
So I have the following:
class Shelf
{
/** @var ...
4
votes
2answers
121 views
How to represent relations between multiple objects without obvious aggregate root
Let's say we have three types of objects:
Agents
Calls
CallsQueues
They all can be linked with each other (1to1, 1toM, MtoM) or have no links, and these links change over time. Calls wait in ...
3
votes
1answer
361 views
How to organize business logic which deals with different, but related objects
The task
The piece of software I'm writing operates on the following object types:
Agents
Calls
CallQueues
These objects can be linked together, and each of them contains some additional ...
4
votes
2answers
373 views
Best diagram to show relations between several applications
I'm currently an intern at a company. For my intermediate report I Received some feedback about displaying the relations between multiple applications.
So in my image all 3D rectangles are a deployed ...
0
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0answers
304 views
Examples for bidirectional and unidirectional relationships between objects
To better demonstrate the difficulties of reading/updating objects in a multithreaded environment, I'm looking for examples for groups of objects with a bidirectional or unidirectional relationship ...
1
vote
1answer
80 views
Imposing conditional entity relations
While working on an application, I am facing an issue. And I am not sure how to solve this.
For explanation I have managed to come up with a simple example below:
Consider a Grocery Store ...
3
votes
1answer
119 views
Looking for a strategy to ensure name of child node stays unique in collection
Even though I'm programming in PHP, I'm open to reviewing language-agnostic suggestions, as they might point me to valuable directions.
To remove any possible confusion I feel some comments appear to ...
3
votes
3answers
228 views
How can I mark one of a 1:n relation as the “default”?
I have an "easy" question, but since I am not a very experienced programmer I would like to hear what some of you have to say.
If I have for example a Db called MyDb with many tables. Two of them are ...
0
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1answer
123 views
What are best practices to maintain a list in the database in Rails?
I have list boxes and model relationships in the database. I'm doing the following migrations to maintain lists, rename items, and add items:
def up
Fund.create min: 0, max: 1_000_000
...
2
votes
3answers
517 views
UML : is it okay to use only Association in a class diagram ?
I feel confused about the three relationships Association, Aggregation and Composition in UML. I need to finish a project soon, until it became less unclear in my head, is it okay to use only ...
5
votes
3answers
14k views
ERD: “many” vs “zero or many”/“one or many” crowfoot notation?
Background
I saw this figure describing the different crowfoot notations used in ERD:
I'm not able to find the difference between the "many" notation and the "zero or many. However I was able to find ...
1
vote
1answer
142 views
Can the has-a relation in OOP become ambiguous or difficult to know?
Assume I have the following code.
class D { static Integer i1 = 42; }
Is it true that D has an Integer? Or is it only for instance variable that we can have a has-a relation?
I also wonder about ...
3
votes
4answers
194 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 ...
3
votes
1answer
520 views
Specifying a bi-directional unique constraint on a join table in Postgres
Problem description
I have a situation where I want to enforce that a relationship can only be defined once and I want to solve it on database (Postgres) level.
The following situation I consider ...
4
votes
2answers
170 views
Designing my classes with relationships
I need to build a UI for entering values to the database. I am stuck with my class design to achieve it.
I need a UI where I am able to enter the name of the system. Each system can have many options....
0
votes
0answers
58 views
How to model relationships in scenario where every product can (don't have to) be associated to only one category
This one still occupies my mind. How do you model 1:N relationships.
Consider having a category and product (typical e-commerce scenario).
Every product can (don't have to) be associated to only one ...
0
votes
1answer
1k views
Database design for linking parent & child relationship
Currently i have requirement saying user from an UI creates there own forms which has types textbox,choicegroup etc..
Does anyone have a any idea on how to architect the database to store all data?
...
1
vote
1answer
1k views
Laravel relationships and database schema
I am playing around with Laravel and came across something in the documentation for defining 1 to 1 relationships between tables that I would like to get feedback on.
The example in the docs is ...
2
votes
2answers
1k views
Is composition and aggregation really a type of association relationship?
From Wikipedia:
There are four different types of association: bi-directional,
uni-directional, Aggregation (includes Composition aggregation) and
Reflexive.
From what I know:
Composition ...
1
vote
1answer
88 views
How to associate both a collection and one item of this collection to an entity
I'm working on a project in which I have an entity, we may call Users and another entity Address.
I want to define the entity User in a way that an user would have a collection of addresses (...
1
vote
4answers
301 views
Domain model associations that do not required the behaviour of the associated object. How to model?
I've been struggling with this question for a while.
I'm specifically thinking within the object orientated domain model.
Let's say I have two entities. A supplier and a customer. There is a ...
1
vote
3answers
306 views
Pattern to safely establish a one to one bidirectional relationship
Let suppose we have 2 classes, Pilot and Plane, being in an optional one-to-one relationship. So a Plane might have a pilot when it's flying, but when it's standing in its hangar, it has none. Similar ...
8
votes
1answer
560 views
Relation between objects
For a few weeks I’ve been thinking about relation between objects – not especially OOP’s objects. For instance in C++, we’re used to representing that by layering pointers or container of pointers in ...
2
votes
3answers
909 views
Should POCO domain classes contain collections?
The question title is not good, but I couldn't think of a way to word it better.
I am used to develop using POCO classes in my projects, that is, domain objects contain absolutely no logic, only data....
3
votes
2answers
917 views
MVC: “User” model gets big and crowded. Should methods that do CRUD operations on one-to-many relationship data be in different models?
In most MVC web projects there is a User class. Many times a user has something else in a one-to-many relationship, i.e. orders.
If we have a user class that has many orders, should methods that add, ...
1
vote
1answer
411 views
Need help modelling a User/Project/Task relationship
So I'm creating a very simple project/task management application in Laravel 4 and I'm not sure how these relationships would work. I have a Project, Task and User model. A User can own a Project or ...
2
votes
1answer
936 views
REST Relationships Besides Parent/Child
This would seem to be a pretty basic question, but I can't seem to find appropraite guidelines for it. What is the "restful" way of POSTing a relationship between two entities that are not necessarily ...
10
votes
2answers
10k views
Database Schema for Pricing Products (packages, promotions, qty based, limited time offer…)
I'm working on a new point of sale for a company that products for different prices depending on the product mix.
All products have a base price.
To explain my problem, I will use the following info:...
4
votes
1answer
436 views
Database Design - Optimise Relationships
I am about to embark on a redesign of an application, one where querying the database is particularly annoying. I intend to redesign the database as much as possible but the data shape cannot change ...
0
votes
1answer
130 views
Keyword Collection, ManyToOne or OneToMany relationship?
I hope this is the right place for this type of problem.
An Object of my class Movie can have several keywords ( like 'fight club', 'brad', 'fincher'), and be part of different categories (like '...
4
votes
1answer
317 views
What is the name of this relationship between objects? [closed]
Different types of dependencies have particular names, such as linear dependency, circular dependency, self-referencing object, etc.
What is the name of the dependency where those rules are true?
A ...
2
votes
3answers
21k views
Relationship DAO, Servlet, JSP and POJO
I want to implement a JSP, POJO, DAO and Servlet in my J2EE program. However, I don't fully understand how the relationship between these elements should be. Is the following (MVC) setup the right way ...
-2
votes
1answer
218 views
Performance impact of not implementing relationships at the database level? [closed]
Let's imagine a data model with customers and invoices. There is a 1 to n relationship between a customer and its invoices. We uses an ORM (like Hibernate).
One can explicitely implement the 1-n ...
2
votes
1answer
238 views
How do you map members and their responsibilities to an organization? [closed]
I'm working on a Django project that tracks arts-related activities, and I'm stuck on the human-resources part of things.
(code below) I have a class Ensemble that subclasses Organization. ...
4
votes
2answers
3k views
Rails and Mongoid best way to implement sharing system
I have to model User and Board in rails using mongoid as ODM.
Each board is referenced to an user through a foreign key user_id and now I want to add the ability to share a board with other users.
...
5
votes
5answers
268 views
Value of maintaining debug outputs
A developer on our team litters his code with debug outputs. He passes many parameters into methods that are only used for debugging.
Personally I find this clutters up the code. If I need to debug ...
7
votes
3answers
11k views
Master, Slave: Politically Correct Version [closed]
What other tech synonyms are there for a master-slave relationship? The situation is a knob that controls other knobs, or a button that controls other buttons.
9
votes
4answers
4k views
I had a bad job interview, but still got the job. How do I handle the relationship with my new manager? [closed]
I participated in a set of interviews for a position in which I was hired recently. During the interview process I was interviewed 6 seperate times. 3 technical interviews and 3 situational / ...
36
votes
14answers
2k views
How to improve relationships between consultants and staff programmers
I have been a consultant for a small software consulting firm for quite some time now. Our normal business model is not staff augmentation, but such that we find clients who need assistance in ...
