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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0answers
27 views

What database should I use for these versioned data feeds? [on hold]

I want to take feeds of products and deals from merchants, and keep them up-to-date with with detected changes. Every time I update a update a product, I want to give it a higher version number. ...
2
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2answers
52 views

Is normalization all that's needed to ensure data integrity and quality reporting?

I've gotten out into the real world recently, and for the first time have had to really think about database design, as I've been developing across the entire Java stack. With that I've realized that ...
-5
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0answers
28 views

Database schema and data management tools [on hold]

I've been using Visual Paradigm to simutaneously manage my database's schema and example/test data during its development. I have found their interface to only get buggier over time and would like to ...
0
votes
0answers
14 views

Cascading ACL and drill-down data architecture

I want to implement a drill-down data architecture based on the data and the ACL permissions of a user. Lets say we have data of employees of an organization and lets consider the hierarchy as ...
4
votes
1answer
95 views

How to store data that is recorded with different frequency?

I'm writing a metallurgical web application, that must store data (electrical parameters) recorded at different frequencies. For example: six parameters recorded with frequency of one measure per ...
10
votes
2answers
398 views

Why store flags/enums in a database as strings instead of integers?

I've been browsing SQL dumps of some famous CMSes, including Drupal 7, Wordpress (some quite very old version), and some custom application based on Python. All of these dumps contained data with ...
1
vote
1answer
95 views

Is there a valid symbol for “two or more” with Crow's Foot notation?

I have a database design for which one entity of Class A always has at least two entities of Class B. Can I express this with valid Crow's Foot notation? One possible idea I had was this: Excuse ...
1
vote
1answer
37 views

SQL - Designing a Threshold value table

I need to design an SQL table to be used for "threshold" or special values, which in general would have the following properties: - key - value - comparer (less than and greater than as a start, ...
0
votes
1answer
56 views

How to represent a Model with a 1:N relation?

I have a task to associate 1:N documents to a record in my hardware table. This file could be a warranty, or whatever. In SQLServer I set up a FileStream group and made a table for only the file and ...
1
vote
3answers
149 views

Are there any good reasons to use ER Diagrams instead of UML Class Diagrams for data modeling? Is ERD the COBOL of data modeling?

Are there any good reasons to use ER Diagrams instead of UML Class Diagrams for data modeling, given the fact that class diagrams subsume ER diagrams? Or is it just for historical reasons because ...
3
votes
1answer
36 views

Architecting a SaaS for backwards-compatibility in regards to data and business logic

I have a SaaS platform where the user fills out a form and data entered into the form is saved to a database. The form UI has a large amount of config (originates from the DB but ends up in ...
11
votes
5answers
386 views

Version controlling a database's contents

I'm working on a web project that involves user-editable content, and I'd like to be able to do version-tracking of the actual content, which lives in a database. Basically, I want to implement ...
0
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0answers
34 views

MySQL Database normalization for a user model

I currently have a MySQL Relational Database with a users table with the following attributes: ID (Primary key) Name Username (Unique) Password Email (Unique) Description Profile Picture File Path ...
1
vote
1answer
25 views

Recording many data items and retrieving time-based snapshots

I have a .Net Windows application that continually receives data from a hardware device. Additionally, the user can change various settings and parameters from within the software. I would like to ...
1
vote
2answers
111 views

Database Design for Inventory

I am starting to design a typical product based MySQL database but I keep running in circles on how to design the tables. I have many types of products Jeans Tshirts Dresses Which have many of ...
3
votes
0answers
121 views

Fine grained search over a large dataset

I have roughly 4 million records per day and have to keep 7 years worth online, so we are looking at 10.2 billion records that I need to be able to search through. The users are expecting that the ...
0
votes
2answers
29 views

Groups relationships - Detailed or Direct?

Current design I have a Person model: PersonId Name ----------- ---------------- 1 Jessica 2 Jennifer Then I have a ShareModel which have the ...
47
votes
7answers
5k views

How can I argue convincingly against duplicating database columns?

I've started working at a new organization and one of the patterns I've been seeing in the database is duplicating fields to make writing queries easier for the business analysts. We're using Django ...
1
vote
1answer
85 views

Likes / Stars / Following - same or separate data structures? [duplicate]

I am building a social network, which will have standard features of 'likes' (upvotes) for posts, 'following' between users and 'stars' for favorite posts. These might reasonably expand in the future ...
1
vote
1answer
113 views

Am I planning my database/backend correctly?

I'm an iOS developer and to be honest I'm not really looking to become a database expert right at this moment, but I do need to know how to properly plan out what I believe to be a pretty cookie ...
4
votes
1answer
41 views

Modular Database, Inheritance of Schema

Consider multiple relational database schemas that have an inheritance dependency structure as known from OOP systems: Tables are just a placeholder for arbitrary database objects such as Views, ...
2
votes
1answer
43 views

Is it good practise to have the class name as a prefix in Django model?

I wrote a model in this format in Django: class Block(models.Model): block_id = models.AutoField(primary_key=True) block_name = models.CharField(max_length=200) block_code = ...
2
votes
2answers
67 views

Notifications table design?

I'm trying to create a notification system for my social network. But I'm stuck on the database design. so when a user comments on another user I want to display "X commented on your post." or when ...
3
votes
3answers
82 views

Secure DAL Design using Stored Procedures

I normally avoid sProcs as much as possible. I dont like the language be it TSQL or PL/SQL; they seem archaic against Java/Dot-Net which I use. I go for them when a routine needs to fetch a lot of ...
1
vote
1answer
41 views

Object Storage where Object Type is variable

From time to time, we come across a problem where we must store an object, but we don't know in advance what kind of object we're going to store. I'm going to give a very simple example. Requirement: ...
1
vote
1answer
66 views

What happens to database design process when ORM tools are used?

I have learned about database design, including normalization during my undergraduate course. When we have to model a database for a system, we can start with an ER model and then convert it to the ...
0
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1answer
41 views

Planning complex Mongo (And possibly other NoSQL) Databases

There is no "right way" to do anything, but there are "better" and "worse" ways, as well as true and tested ways. I'm studying Mongo and considering it for a project. It's gonna start small but ...
1
vote
2answers
74 views

What is better for scalability for this specific dataset, MongoDB or MySQL?

I have a web app which has users, forms, and volunteers signed up on those forms. Currently I am using MongoDB and have it setup with a collection for admins, and a collection for forms with ...
0
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3answers
115 views

Is the Model part of MVC an inner platform

I'm not particularly up on MVC as an architecture but isn't the Model just a duplication (except slower and buggier) of the database? Given modern databases support stored queries, user definable ...
4
votes
1answer
224 views

How does the team ensure a good DB design? [closed]

We want to ensure that our team delivers a good performing DB design. But we are not quite sure how to achieve this. Couple of solutions have been suggested within the team: Adding DB indexes to ...
6
votes
7answers
331 views

How would you design a user database with custom fields

This question is around how should I design a database, it can be relational / nosql databases, depending on what will be the better solution Given a requirement where you'll need to create a ...
1
vote
1answer
46 views

how best structure localization of content type category name

I'm working on swift / iOS with a parse.com backend but this question could be applied to any language and is a general conceptual question. I'll use a specific example for illustration purpose. I ...
3
votes
1answer
133 views

Do you still need created_by and updated_by attributes with dedicated auditing?

For as long as I have been writing database-backed websites, I have included created_by, created_at, updated_by, and updated_at in every single table. As you can guess, whenever a record gets created ...
1
vote
2answers
50 views

How to handle inmutable data on Databases

I'm working on a quotation software. It basically creates quotations for customers based on certains ProductModel that contains n Plan that contains n PriceRange Edit: Here's a ER diagram of the ...
1
vote
3answers
91 views

Chat-service database design

I have an android/desktop application that I'm now releasing on the web, and as there are some social aspects I thought of adding a chat-service so users can IM as well. For this chat service, I want ...
58
votes
10answers
6k views

Is it premature optimization to add database indices?

A colleague of mine today suggested that we go through all of the queries in our application and to add indices accordingly. I feel this is premature optimisation because our application is not even ...
1
vote
1answer
115 views

ER Diagram Multiplicity (UML)

Schema: #=PK Employee (#NIN, fName, lName, address, DOB, sex, salary, taxCode, deptNo) Department (#deptNo, deptName, managerNIN, businessAreaNo, regionNo) Project (#projNo, projName, contractPrice, ...
1
vote
0answers
28 views

Database data Bucketing Report Design

Here's the scenario: I have item x (item_id, customer_number, cost) which can be submitted to another system multiple times over months which may or may not reject item x before finally accepting it ...
1
vote
3answers
86 views

Performing data operations that involve separate applications and data sources

I'm designing an enterprise application that produces output based on some input data from another application. In this case, I happen to have also built and thus do control the source application ...
0
votes
2answers
59 views

DB Schema for a questionnaire - Different output from different combinations of responses

A user is required to complete a questionnaire - answering the questions in various categories. Depending on the responses from the user, the user will be presented with a number of recommendations. ...
0
votes
1answer
46 views

Database structure for links between objects of same class

I have seen elsewhere that it is a nice design to implement links between objects in a database as a separate object. This makes a clean way to have multiple objects of one class to be linked to an ...
1
vote
3answers
172 views

Is self referencing tables a good idea for geographical data?

I am creating a design for different Geographical types where each type is just a little "place holder" in over all heirarchy. One example is Zip code Belongs to Territory Belongs to District ...
3
votes
2answers
90 views

Encrypting stored data for multiple unique users to access information

Developing a database for many users, and thousands more "people" in the database, one section requires we encrypt the personal data - Youth's information, medical information, etc. We have users who ...
5
votes
2answers
278 views

Hard Coded File Paths - Solution?

Say you have an application that saves image(.jpg, .png etc) and text(.txt, .xml) files, and the application has all of the files paths hard coded throughout code, per the example below. Assuming the ...
0
votes
1answer
37 views

Merging user activities into one stream with a common representation

My social network website currently has forum threads and posts gallery pictures albums on the users' profiles group discussions classifieds I would like to create one "stream" of activity. It ...
0
votes
1answer
74 views

Application with really dynamic data structure [closed]

Well, I'm on the verge of this project that really puzzled me. The situation is, in our office, we have a department that collect data about the corporate performance indicators from all across the ...
0
votes
1answer
54 views

Is there an established pattern for associating a database entry with a Java class that executes on that data?

I have a behavior tree with different leaf nodes that execute tasks. When building out the tree relationship in the database I need an association between the leaf node entry and the Java class that ...
1
vote
2answers
75 views

Structuring data to represent a tree with squirrels

What I want to represent Let's assume I have several schemas of the following kind: It is a tree on which positions of squirrels are represented by a blue dot. The number of bifurcations differ ...
3
votes
3answers
249 views

Do I need use really INNER JOIN?

Imagine a coiffeur, with his services: +----+-----------------+--------+ | id | name | amount | +----+-----------------+--------+ | 1 | hair cut | 40 | | 2 | shampoo | ...
2
votes
1answer
94 views

What should be the structure of a person to person store database?

I am going to create a person to person store with Laravel, a website where its users can share and sell their product or their mobile, TV, Computer, Shoes, Shirts, Books, Cars, Bags, Animal, etc. I ...