For questions about structuring the data within a database. How to lay out tables, whether to use a relational DB or not, etc.

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2
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1answer
135 views

Is it substandard if I have multiple tables in my database yet there's no relationship at all? [closed]

I have multiple tables in my database. Some tables have relationship to others and some don't have. My friend told me that it is not advisable to have a table that is not related to others. Is it ...
0
votes
0answers
164 views

Avoiding pitfalls of a naturally recursive relationship between tables

I'm developing a system to manage "cases". There will eventually be many different "kinds" of cases, so I've started with a "CaseTemplate" table that can be used to define what a case looks like and, ...
3
votes
2answers
2k views

Ruby on Rails database using static lookup tables or constant strings

In some ruby on rails projects, I have seen instances where strings are used instead of a foreign key reference to a lookup table. I usually code in C#/SQL Server and use lookup tables, but am not ...
1
vote
1answer
50 views

How to represent one special related record

I have two tables, project and photo. photo has ID,projectID,path : each project has multiple photos. Now one of these photos is the one that has to be displayed. The question is how to represent ...
2
votes
2answers
332 views

Implementing bussiness logic with a large number of business rules and processes

We are currently working on a project that heavily relies on a database. Among many tables the main focus is on table "data" which is linked to another table "data_type" as many-to-one, which is then ...
0
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0answers
66 views

What's the best way to hold features in a database?

taking for example an application that holds Companies and as we move along time, more and more features are needed. I do tend to hold everything in the Companies table, but I rather get some input ...
0
votes
2answers
190 views

Store the result of a complex but frequent database query, in another temp persisting table

I have a slightly complex SELECT query which uses a number of JOINs and variables inside it and the query is run frequently throughout the application. The result varies when one column is updated. ...
0
votes
4answers
323 views

should I store common data between two tables in a third separate table in my database?

If I have 2 tables in my database, let's say for instance 'buyers' and 'sellers' but I collect a common set of data for both for instance telephone number, email address, address etc. Is it better ...
4
votes
3answers
503 views

Is it better to use a switch statement or database to look through 5,000 to 10,000 instances?

I have some JSON data in this format (5,000 instances for now): {"id":"123456","icon":"icon.png","caseName":"name of case"} I am allowing the user to search for the name of the case and then return ...
2
votes
1answer
822 views

Data Model for selling groups of products as one product

Say I have an e-commerce with a data model like the following, which allows a Sale to describe how a single Product is sold. This division allows a product to be sold multiple times in different ways ...
1
vote
2answers
325 views

How to store currency ranges in a Postgres table?

I am using Postgres 9.3. I have to store range data like <$250K, $250K-$4M, etc which we will display in a dropdown. now I am making a table for all possible options that can be configured from ...
6
votes
2answers
5k views

single table w/ extra columns vs multiple tables which duplicate schema

I am working on a project where at some point, I needed to make a decision on whether or not, in the database, I should have a single table with multiple columns that not every record uses, or ...
4
votes
3answers
2k views

Designing a fitness / weight lifiting routine database

I'd like to create an app similar to Barbell Pro for Android, for practice / interest / educational purposes really. Or even as another example for database purposes, Fitocracy The problem is, I ...
3
votes
3answers
620 views

Tracking correct order details in commerce database when modifying 'products'

I am implementing an ecommerce database. This is slightly different than most as the 'products' that are for sale are for services provided. For example a user (vendor) of the system may define a ...
0
votes
1answer
230 views

Relationships in a Chen ERD

I am working on a Chen ERD to model our organizations merchandise. Our central entity is a Style. We have supplemental entities of Color and Season. I am defining our assortment as the ...
7
votes
4answers
3k views

When should a database table use timestamps?

First a note, I thought maybe this question belonged in the database exchange, but I think it is more broadly related to a programming solution as a whole than to databases. Will move to database ...
4
votes
1answer
822 views

State pattern vs Inheritance

In the following image for the State Pattern from Applying Domain-Driven Design and Patterns: With Examples in C# and .NET I'm trying to persist the SalesOrder entity into the database. Normally I ...
2
votes
3answers
146 views

Refactor an old model of a LastUser Modification on every Object?

I have a software requirement, that needs to store the user that made the last modification to another object, for every object (assume that all objects are already mapped and into a BD). So we have ...
0
votes
1answer
4k views

Practical mysql schema advice for eCommerce store - Products & Attributes

I am currently planning my first eCommerce application (mySQL & Laravel Framework). I have various products, which all have different attributes. Describing products very simply, Some will have a ...
-4
votes
2answers
3k views

Best way to keep large amounts of data (no relational database needed)

I would like to know what should be the best way to keep data on a server related to the following points: Chat logs Heavy text content User references like amounts of ids (1,4,14,524,23220,...) ...
3
votes
5answers
251 views

Violating SQL principles

I have to write a decent size database, 1GB more or less. I have only taken an introductory semester regarding SQL databases. During the course we learned that the relational model under SQL has no ...
0
votes
2answers
189 views

A hint to create a db schema

I need to realize a database in this mode: TABLE restaurant with "classic" fields of a place: address, street number, phone, website, etc etc etc. I need to indicate also the days of opening // ...
2
votes
2answers
131 views

How to represent compound elements within a database?

I need to design a database table that holds the data of programmers work hours. The problem is that I have a compound type - two pieces of data belong to a category. Specifically, the work hours ...
2
votes
1answer
3k views

What is the difference between UML Data profile and ER model?

I have been asked this question and even after a lot of research, I cannot find the answer. When I design a database using Entity relationship (ER) and then re-draw it as UML class model (extended ...
10
votes
1answer
388 views

Preferring Database Normalization vs. Schema Transparency?

A new requirement has surfaced on an old codebase, that basically enables direct (internal) communication between two formerly not-directly related classes of users (stored in different tables with ...
0
votes
1answer
108 views

Do we have any special design considerations for maintaining anonymity in an application?

This is an open-ended question which I am analysing while doing some fun projects in leisure. Websites like Google, Facebook do store user activities and perhaps sell them or use them for ...
2
votes
1answer
75 views

what's the proper way to organize code that straddles multiple objects?

Let's say I have the following classes: person, widget, foo_bars. A person can have multiple widgets and foo_bars. When an admin deletes a person, I want my code to do a cascading delete... and ...
3
votes
1answer
170 views

What is the standard practice for extracting an auto-incrementing primary key?

I have some objects that will be created an entered into the database. There is no guarantee that any of their fields will be unique except for the auto-incrementing primary key. I would like to be ...
4
votes
4answers
495 views

eCommerce use case: removing a product

I am starting to design the database schema for the eCommerce element of a web service I am creating. The thing I'm trying to get my head around is how to deal with the use case of a seller (user of ...
2
votes
2answers
782 views

MongoDB: Is this a good schema design?

I'm working on a Meteor app which lets users create events and assign them crew members. I've played around with MongoDB before and made some experiences along the way, where for instance my first ...
4
votes
4answers
489 views

Typed search over complex model. Possible CQRS / NoSQL solution

Given the following relational model: I need to implement a typed search for hotels, which should be able to query on name, city, country, category, hoteltype, roomprice, customtype, room custom ...
1
vote
2answers
215 views

Should a DR & CR entry both be created or a single-entry accounting is fine

A new project has an amount. It is always related to a client. One client can have many projects. And he may pay in steps for a particular project. In order to keep track of client payments, I've ...
2
votes
1answer
176 views

Design Application to “Actively” Invite Users (pretend they have privileges)

I am designing an application where users message one another privately, and may send messages to any Entity in the database (an Entity may not have a user account yet, it is a professional database). ...
2
votes
1answer
154 views

How to handle when one user deletes the object while the other has it opened in edit mode in a webapp?

I am developing a CRUD type web application. It is a project management system having projects, milestones, tasks, employees etc. Each employee has his/her own account to login and view the system. ...
0
votes
1answer
207 views

How to store Status for Reservation table

I have a reservation table (a user fills out a form to request a reservation). It has two parts that need to be confirmed. isReservationAccepted (decline,accept,waiting) and hasReservationBeenSent ...
3
votes
1answer
3k views

Database design/relationship for threading messages

What's the database design or business logic for creating an app for messaging between users? I am having difficulties with choosing how to approach the relationship between each Conversation of User ...
4
votes
3answers
873 views

Designing a database with circular references for the-one-of-many case

Consider the following case: there are two models Image and User. Users have associated images and they can pick one of them as their profile image. There are essentially two ways of modeling this: ...
2
votes
3answers
370 views

Which database schema should I pick?

I am planning a database scheme and I hesitate between two designs, which one should I choose? For the purpose of the question, assume we want to prepare a database scheme for an application managing ...
2
votes
2answers
114 views

How should this relationship be structured in a relational database?

In a recent project I was asked to implement an events system. An Event had to have a Location which was originally specced out as simply a physical location with some optional extra notes. Then the ...
0
votes
1answer
95 views

Multiple schemas vs aditional column per customer

If you have different database per customer as there is no need to share any data between them does the same apply if a customer has multiple stores ? I believe that it is easier to do queries for ...
0
votes
2answers
711 views

Is storing stack traces in database recommended?

The current system I am working on goes through a set of documents & performs some logic using the metadata of the document. If the metadata of a document is fishy..it throws an exception. The ...
0
votes
1answer
287 views

How does this normalized example work?

I had the following DB schema: Customer Car Rental ------- ---- ------ Name Name Car_ID ID ID Customer_ID Date This is said to be non normalized ...
2
votes
2answers
763 views

How should I make searching a relational database more efficient? [duplicate]

This is in the scope of a web application. I have a database which has a few nested relations. There is a feature which depicts the history of a large chain of relations. It is essentially a data ...
0
votes
2answers
182 views

How should I structure my database to gain maximum efficiently in this scenario?

I'm developing a PHP script that analyzes the web traffic of my clients websites. By placing a link to a javascript on the clients website (think of Google Analyses), my script harvests information ...
5
votes
3answers
485 views

How to conciliate OOAD and Database Design?

Recently I've studied object oriented analysis and design and I liked a lot about it. In every place I've read people say that the idea is to start with the minimum set of requirements and go ...
4
votes
2answers
3k views

Database model for keeping track of likes/shares/comments on blog posts over time

My goal is to keep track of the popular posts on different blog sites based on social network activity at any given time. The goal is not to simply get the most popular now, but instead find posts ...
0
votes
1answer
157 views

Implementing new required feature after software release

Fake Scenario There is a software that was released 1 year ago. The software is to map and register all kind of animals on our planet. When the software was released, the client only needed to know ...
1
vote
1answer
333 views

Store data for multiple User Type

I am developing an app where four types of user share same module. So is it a good idea to create: one table and user_type and user_id (something like that) table prefixes basically 4 diff tables of ...
2
votes
0answers
54 views

Best Way to Handle Meta Information in a SQL Database [duplicate]

I've got a database where I want to store user information and user_meta information. The reason behind setting it up in this way was because the user_meta side may change over time and I would like ...
8
votes
4answers
595 views

What exactly does it mean that storing “large blobs in the database reduces performance”?

To someone who knows database internals this may be an easy question, but can someone explain in a clear way why storing large blobs (say 400 MB movies) in the database is supposed to decrease ...