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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3
votes
1answer
82 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 ...
-5
votes
0answers
22 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 ...
1
vote
1answer
286 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 ...
0
votes
1answer
150 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 ...
4
votes
4answers
220 views

Two possible solutions to a problem, DB design

I saw the recent post about the person questioning his boss's solution (I believe my solution is better than my boss, so should I ignore him?) and decided to ask something similar but not as ...
10
votes
2answers
388 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
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 ...
7
votes
3answers
1k views

How to separate sensitive data in database(MySql)

I need to design a database that will contains information about personal disease of users. What can be the approach in order to implement the columns of the DB's tables: encrypt the information, ...
5
votes
2answers
276 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
55 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 ...
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. ...
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 ...
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
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 ...
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 ...
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, ...
1
vote
3answers
146 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 ...
11
votes
5answers
384 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
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 ...
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, ...
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 ...
23
votes
6answers
1k views

Does the advent of the SSD have any implication for database optimization?

Today I was browsing through a book on SQL Server optimization and it seemed that a certain amount of the ideas were based on a linear model of storage. As SSDs have a completely different storage ...
1
vote
2answers
101 views

How can you predict the time it will take for two processes in two different machines in a cluster to communicate?

I am trying to develop a computing application which needs a lot of memory (>500gb). Buying a single machine for that is overly expensive. I can, though, buy ~100 small instances on Digital Ocean or ...
4
votes
1answer
228 views

What is a buffered write scheme?

I received this response from Jeff while researching hit counters. He said page hits are incremented in a buffered write scheme, and that a views table does not exist. Can you explain what a buffered ...
0
votes
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 ...
0
votes
3answers
158 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 ...
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
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 ...
19
votes
6answers
7k views

Should I use one database per application or share a single database amongst multiple applications [closed]

I have multiple applications some that use data from the same sources. Is it best practice (or what are the pros/cons) to: leave the data in databases shared by multiple applications saves space ...
10
votes
4answers
8k views

Multi-tenancy - single database vs multiple database

We have a number of clients, whose systems share some functionality, but also have quite a degree of diversity. The number of clients is growing - always a healthy thing! - and the diversity between ...
1
vote
3answers
126 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 ...
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 ...
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 ...
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
112 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 ...
0
votes
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 ...
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
votes
1answer
94 views

Best solution for future maintenance of a website with hardcoded ids, custom CMS using bad database design [duplicate]

Recently I was put into a position of a tech-lead on a very interesting project that I have been partially working for two years. This project carries a lot of legacy stuff with it even though we try ...
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 ...
24
votes
8answers
5k views

Front end first or Back end first. Of the two which is a Good system design pratice?

I have a client right now requiring me to develop a school enrollment system. Now this is the first time im having this kind of challenge. Most of the past software that i created are not that ...
0
votes
2answers
107 views

Implement a virtual tag on the database level

I have a set of objects, for which users manually applied tags, whatever they invented. I'd like to implement a task engine, where each task might be applied to objects from a tag. For convenience, ...
6
votes
7answers
328 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
211 views

Data model for persisting queries to database

I have been asked to build what is essentially a query builder for a reporting application. The variety of objects to query, potential modifiers, number of conditions, and so forth to be reported on ...
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
votes
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 ...