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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1answer
91 views

Class Table Inheritance: do child tables need a primary key?

I'm using the Class Table Inheritance architecture with my application and have read Fowler. When mapping my database tables to classes in code, I've realized I have no need for an "ID" property on ...
2
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4answers
286 views

Are NoSQL databases the best choice for more efficiently querying large amounts of data?

We are planning to build a travel website in which we will be integrating multiple APIs (eg. DOTW, GTA, Expedia) for Hotels. I have initially tried to use MySQL but since there are huge amounts of ...
1
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4answers
156 views

Database design for objects with multiple states

Context I'm designing a database which, simplified, should be able to handle users sending job requests to each other, and after that a job can be started, finished, and reviewed. The design should ...
1
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1answer
252 views

Is this database design good? What JPA Entities should I create for this design?

I am trying my hands on JPA. For this I am thinking of using the example of a student admission process as shown in the diagram below. Is this design good ? Any suggestions for improvement are ...
2
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3answers
169 views

Effect of denormalizing

Here's a scenario where I'm wondering whether to denormalize a relational database (MS SQL). Text description of the requirement I have users (stored in a users table). Users belong to Accounts: ...
2
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0answers
111 views

Is this a good implementation of mongodb for a money management tool?

I have a money management tool which has users. Each user may have several accounts/funds (e.g. bank account). For each account/fund there may be thousands of transactions. Users may only view their ...
3
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1answer
254 views

What is exclusive arc in database and why it's evil?

I was reading most common database design mistakes made by developer Q&A on stackoverflow. At first answer there was phrase about exclusive arc: An exclusive arc is a common mistake where a ...
1
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2answers
435 views

many to many relation in database schema and oop class diagram

I have Student and Group entities. Student can have many groups and Group can have many students too. so in database I should have middle class and change many-to-many relation to one-to-many and ...
1
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1answer
162 views

A very simple database system with JSON

If we need to store some data in a database, but without the need of advanced SQL features, can we use this scheme (written here in Javascript / node.js) : // the DB will be in RAM ! var myDb = {}; ...
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3answers
147 views

What is the hierarchical DB schema for this xml?

As per this link, this is the xml that maintains "BookStore" data. I see that number of occurences of author are varying for any book. xml's hierarchical representation of BookStore looks more ...
1
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3answers
125 views

Best approach to implement an update operation of a container object?

I have an Invoice object wich may contain several FacturedServices objects stord as a list. In may interface, the user can edit an Invoice object, delete add or edit its FacturedServices list. Whe ...
3
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1answer
43 views

(HTML) Form structure storage

In the context of a single-purpose website/application (for instance, based on Symfony2), I wish to have a set of forms fillable by users which then will be sent out as a formatted email (with the ...
0
votes
2answers
224 views

Dealing with several custom getters

I have a data structure with data units containing different types of data. I've wrapped the data in "Field" objects so that each field is able to independently parse user input in a desired way. ...
2
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3answers
141 views

Best approach for storing huge data

I'll be handling 300,000+ users. Each user (after logging in) will be able to create lets say "folders", in each folder, users will create "name=value,name2=value2,name3=value3" entry pairs. Each name ...
8
votes
3answers
912 views

Decentralized Data Management - encapsulating databases into microservices [closed]

I've recently been taking a course on Software design and there was a recent discussion/recommendation about using a 'microservices' model where components of a service are separated into microservice ...
2
votes
2answers
279 views

Creating a separate table for images or adding “image fields” to many tables?

I need to create a database in which several tables have images. For example, users have profile pictures and uploaded ones and products have many pictures, as well. Is it better to have one MySql ...
4
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2answers
123 views

Using audit trail as time machine?

I would like to do SELECT * TABLE t (using data from 1st of march 2012) I already have a nice audit trail of all tables in the database. It basically makes a copy of all rows that change, storing ...
54
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7answers
4k views

Code First vs. Database First

When I design and create the software I work on, I typically design and create the back-end SQL tables first and then move on to the actual programming. The project I'm currently working on has me ...
3
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2answers
93 views

Database design for polymorphic data

I have an application that needs to log communications with users over several different mediums: Email, SMS, Voice, Website Announcements, etc.. in a traditional database. I have considered 3 ...
0
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0answers
31 views

I have two applications… use NoSQL or RDBMS? [duplicate]

I have two applications in the making: one is a budget management tool; the other is a article based places/restaurant guide. The budget management tool works where users create accounts (e.g. bank ...
4
votes
3answers
138 views

How to track temporal changes in a database?

Imagine a software for theater owners. You can accept reservations for the different cinema halls. Each hall has a different number of seats. Say the owner wants to know how many people visited the ...
2
votes
2answers
210 views

Should I use relational or noSQL databases for this problem

I'm working on a project where one part is to save data of different people. A typical person might have the following structure: Email: Multiple values possible City: Multiple values possible ...
2
votes
1answer
220 views

How to represent an optional-to-optional relationship in a database

I have two types of users: a CRM user and a system user. We have a record of every CRM user, thanks to a nightly sync that we run (so we don't have to hit the CRM API every time). We have system users ...
0
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1answer
56 views

user verification value - where to store [closed]

Quick question as relates to database. Where would you store the value of "UserVerified"? (The one that occurs after the user has checked his email and clicked on the "Verify" link with the hash ...
0
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2answers
72 views

How to Design Database with User-Contributed Content

I'm building an application where there are different "Locations". There are Stores, Bars, Schools, and Churches (and so on) all of which are geocoded and defined by existing data sets. While not ...
-1
votes
1answer
110 views

Best way to track 200 boxes [closed]

I have a php/mysql application that needs to track a simple on or off setting for 200 boxes. I use it for a fundraising application. Basically there are 200 buttons. A user selects a button numbered ...
1
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1answer
48 views

Looking for advice for the following MS SQL Schema

We currently have the following SQL Schema: Projects Budgets BudgetTabs BudgetSections BudgetTasks BudgetTaskDetails ...
1
vote
1answer
63 views

Proper tree NoSQL structure with focus on full-text searching

I developing an app with tree(folder-file) structure, on which I should perform full-text searches with MongoDB. I did a research on the best tree structure practices and found this great article, but ...
0
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4answers
116 views

Is there an accepted design pattern for storing a few global variables in a NoSQL database?

I'm wanting to create an admin dashboard for my app, and to show new events there. In order to know which events are new, I'll need to store at least one extra datapoint to the server: the last date ...
3
votes
2answers
269 views

Integrating Holidays and Attendance in an HR Management System

I'm developing a small HRMS system for my company, and am currently thinking of how to integrate attendance and holidays. We currently have an in_time/out_time based daily attendance system, but the ...
2
votes
3answers
256 views

What are the advantages/disadvantages of creating a new set of tables for each user?

I'm working/playing on an app where individual users' data will be completely independent from each other. Of course, there will be common tables for other parts of the app (e.g. "users"), but for the ...
0
votes
1answer
132 views

Would it make sense to have a database table with only one record for tracking site summary stats?

I'm creating a web site that deals with monetary transactions. Users can deposit funds into a wallet and use them on the site. I'd like to keep track of some stats for the web site, like revenue and ...
3
votes
2answers
208 views

Designing a system to archive databases with referential integrity

I have a very large Oracle database, with many many tables and millions of rows. I need to delete some of the rows end-to-end. By end-to-end, I mean, if I want to delete a row from a table then I must ...
0
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0answers
37 views

Managing allocation calendars for an employee set [duplicate]

IN view of creating a MIS (Management Information System) one architectural/design issue that's confronting us is managing allocation for set of employees. Scenario: Employees get allocated to ...
0
votes
1answer
104 views

Best way to structure many-to-one allocation of users to projects in NoSQL

I apologise if this is a bit of a stupid or broad question, but I'd like some general feedback please! Say I have this DB structure for users (in Mongo/JS, but really it's all pseudocode- and the IDs ...
0
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3answers
152 views

Representing category splits in a personal finance database

I'm working on developing a personal finance applications (e.g. Quicken/Mint.com/etc..). I plan to store the data in a SQLite database. I'm stuck trying to determine how I want to represent splits in ...
13
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3answers
2k views

Database schema for a ToDo list

I am trying to make a very simple todo list application with PHP, MySQL, Jquery templating and JSON... However, my schema seems to complicate things in JSON. What's the best way to do it? A new ...
2
votes
1answer
188 views

Architecture: Storing all properties as JsonProperty in NDB?

I am storing the data for my app in Google's NDB, but am confused as to what architecture to use. The app data is mostly text based, but has some non-text properties like DateTimeProperty, ...
6
votes
4answers
437 views

Heterogeneous Associations - Data Modeling When an Object that Must Relate to One of Many Classes

Suppose you have 3 classes: ClassA, ClassB and ClassC. Now suppose you have a class Message. You want a one-to-many relationship between each one of those three classes and the Message. The goal is ...
1
vote
3answers
559 views

Database design: 4 types of users but have different functionality , separate or one table?

I have 4 types of users: Admins , normal user , company , service provider admins and normal user share some attributes (id .first name ,last name ,phone ,mail) company and service provider share ...
0
votes
1answer
209 views

RDBMS (MySQL) logic question. How to join multiple “FRIENDS”

so this is a logic question as to creating the proper relationships in a MySQL database. What logic would you choose for the following scenario? This is a back-end for an app where people can have ...
1
vote
1answer
69 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 ...
5
votes
2answers
262 views

Database Normalisation - stuck with “categories”

Context: I'm working on a database of museums and Categories will be one way the user will be able to search. e.g click on "Music" and a list of music related museums turn up. Pretty simple. ...
3
votes
1answer
262 views

How to store a potentially large amount of optional properties of objects?

I'm using Entity Framework Code First with ASP.NET MVC. This handles my database design based on the domain models within my application. As it stands, the engine I'm writing will have a website ...
3
votes
2answers
102 views

Database Design for Inheritance

In my project I have an object Player (attr example: pl_id, pl_data1) that is one of these types: Its GoalKeeper (attr example: gk_data1) OR Defender (attr example: df_data1) OR Forward (attr ...
0
votes
1answer
57 views

is there anything called logical schema and the conceptual schema of a database table?

i want to know whether there is anything called logical schema and the conceptual schema of database table. if so what is it.i searched lot of places for this specific two words, but did not find ...
0
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2answers
62 views

combining user data from user table and user_profile table to just one table [closed]

We are using two table to manage user data. A user table that has a username, email, password. Then a user profile that has first name, last name, bio, etc. Due to some other requirements it has been ...
2
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0answers
75 views

Best approach for displaying a price from a product according the “setup”? [Designing the DB table and relations]

I'm basically building a reseller website, in which people can buy (users) from a predefined product list and sell them at a higher price (clients). I will show you some images to explain better ...
2
votes
3answers
717 views

Best approach for an online store which changes its product’s price over time? [Designing the DB Table]

I am currently creating a website which will allow people to buy consumer products (deodorant, shampoo, toothpastes, etc…) from a store. Those products tend to change price and other details twice per ...
1
vote
1answer
99 views

Representing list of polymophic objects in db

Let's suppose I have a list of derived objects from some base: class Circle : public Shape; class Rectangle : public Shape; There is object, which has vector of Shape * as member variable: class ...