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
28 views

Use redundant data in database design when have multiple relation

In my web application users can submit their advertises and buy package for advertise (packages are used for priority of showing advertises) Database schema is like this: **Package: id, title, ...
3
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2answers
45 views

How to add users to a mapping table?

In the accepted answer to "Encrypting stored data for multiple unique users to access information", @lserni describes a mapping table for users. But among the operations for the table, they didn't ...
0
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1answer
34 views

DB Data structure for .Net sequenced list with insert, delete, move

The problem is maintaining in .net a list of rows that have a specific sequence where rows can be inserted, moved and deleted, and being able to save and restore that sequence from disk. In memory ...
0
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1answer
36 views

Should we sanitise and clean data or only display it in the expected format?

So my problem is, I have users entering their data(names, address) in a mixed form- some with first letter in caps and some without, some inserting more than necessary spaces and so forth. Also, ...
6
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4answers
224 views

Is it too verbose to always have 'modified' time stamps on all entities within a database?

The question can be summarized as: In a database (regardless of type), would it be considered a good practice to always include updated, created (and possibly deleted) properties, for all entities,...
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1answer
31 views

designing a data warehouse: action or status based

I am designing a data warehouse for a sales platform. There exists a group of users that offers and group of users that demands entities. The production data base holds two sources of information: ...
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3answers
31 views

Including record data in the ID number

I'm working on a project that requires assigning ID numbers to records about people in a database. Each person may have many records associated with their ID number. There was a discussion about ...
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0answers
33 views

Strategies to manage approvals of orders together with a log

Backgound I need to develop a system that handles orders that needs to be approved by supervisors (or users with more privileges). A log have to be implemented to show who created the order and when, ...
6
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5answers
130 views

DB design: what is a good way to handle properties for game?

I must persist handful of properties for several games in relational DB. No other type of DB can be used. Number of games will be around 4-5, and number of properties is (for now) kind of small, but ...
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2answers
74 views

Micro-service database management?

Most people say when building micro-services, that it's best to have seperate databases for each of the microservices. E.g: User-microservice: DB - User userId name Etc... Review-microservice:...
0
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1answer
38 views

User, user Role and user Info, data base design problem

I am creating an application that will manage job interviews and help the employers to choose the job seekers based on a ranking system that's based on some user info. I've created a database that has ...
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1answer
101 views

A large Oracle database with no foreign keys [closed]

I am struggling to understand the design of an Oracle database that I have been working with for the past 9 months. The database is for our business management system and I work with it mostly for ...
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0answers
36 views

Design a System to save a data that will be missed from another system

I'm building a middleware system where I'm saving the data from VERY slow API, The system behind this API works like this It produce a data blocks, lets denote a datablock by A. While A is used by ...
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0answers
23 views

What is good practice when saving textual data which contains meta information?

This is bugging me for quite a while and even though I decided to do it in a certain way I am still no convinced that I decided well. Here is the background to it: One of the core features of my ...
1
vote
1answer
95 views

What Graph Theory approaches or algorithms are useful for designing a House?

I have a set of data about a family, and I want the software to find a house design that fits the data (which includes stuff like preferences and whether they want a pool. The current way I am going ...
2
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1answer
68 views

Designing Storage for Different Time Systems

I've been considering doing some kind of application that allows users to track events in mythical settings. However, not all mythical settings allow for normal times. What if one user wants star ...
0
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2answers
111 views

Create a separate table for employees work hours?

I have a table with employees information: id, active, first_name, last_name, gender, id_number, address, picture, password, comment Every employee has an entrance time and an exit time for each ...
1
vote
1answer
47 views

Database Object That Reads From Two Tables and Writes to One

I am updating a database design that must be compatible with old and new applications. My goal is to make a design change which minimizes impact on the existing code. The Design Change Currently our ...
2
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1answer
60 views

Best approach to store huge amount of denormalized/dynamic data with relational database

Here I have a very basic ILS (Integrated Library System) done a long time ago (made with C#/SQL Server), in production for years. But now I have a demand of make this system MARC 21 standard compliant,...
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2answers
61 views

Conditionally show questions based on previous answers in a database driven survey

I'm trying to design survey-type application that uses user responses to determine what the next question should be. For simplicity's sake, question types can be either combo boxes (they have a set ...
1
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2answers
40 views

Creating a web application with full text search on dynamic data

Even after thorough requirements engineering we end up with users wanting to attach 'notes' to their otherwise well-structured data records, in other words: arbitrary key-value pairs. Their primary ...
0
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1answer
48 views

The best approach to make a report based in dynamic data

I have an Asp.Net MVC application where I need to create a report. This report will show some data about an entity (activities), but only activities of ONE specific type that will be inserted in the ...
2
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0answers
70 views

Logging Database Changes

What is the proper way of storing a changelog, similar to git, for data in a database. Currently, I have it set up so that every line in a table is given a unique string id that is used to ...
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0answers
57 views

Saving tabular, spreadsheet-like data in a relational database?

I'm hoping this question isn't too broad or too prone to opinionated answers, since I could really use some pointers. I'm trying to come up with a way to persist tabular, spreadsheet-like1, data in a ...
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2answers
102 views

Database design, processor vs inconsistency

I was wondering, if I have a table that stores, lets say, a user's transactions, then when I need to fetch the user's current balance I would have to go and use SUM() like SELECT SUM(value) FROM ...
2
votes
2answers
44 views

How should I structure a DB schema to include multiple market segmentation data?

A client has recently expressed a wish to assign their market segmentation labels to their customers, so that they can sort by market segmentation in their dashboards ("show me all the VIP customers ...
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1answer
55 views

How to associate similar data with different tables in a database?

My application has users and ads. A user has a unique email. An ad belongs to a user (so, the ads table has a user_id FK, that is simple). Every ad can also have multiple emails and phone numbers ...
1
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1answer
52 views

How to model the database tables for calculating on peak and off peak usage data

I am using MS Sql Server and my system contains power usage data in one table as timestamp and values for KW(two columns). This data is collected at 1 hour interval. At the end of the month I need to ...
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3answers
320 views

How to share a code base among 10+ projects and minimize pain?

I have a number of applications that share the same data in the same database. To try and minimize redundancy of code the Data Access Layer is a shared project. This prevents each project from needing ...
5
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6answers
180 views

Should I add a “boolean meaning” to another column?

Is it a good/bad practice to add a "boolean meaning" to other fields? For instance, let's say I'm modeling events, that might be recurring or not. I can have: A boolean column that holds if the ...
3
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1answer
98 views

Getting posts from users that are being followed: two different implementations

I have two different implementations for retrieving posts from the users someone is following and I want to know which one you would recommend using. First I'l show you the tables, and then the two ...
0
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1answer
93 views

Entity Framework Code First, C# class separation and EAV

I'm in the process of redesigning a portion of my ASP.NET MVC application. I'm currently using Entity Framework 6.1 code first approach. I've been reading as of late that (Correct me if I'm wrong, I ...
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3answers
92 views

Are crow feet notation and uml notation same?

Does crow feet lies under the sub category of the UML notation or it is a whole other approaches. As far i have seen only difference between two of them is that crow feet uses crow symbol |------<-...
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5answers
130 views

Database design - When should a table column actually be a table?

Compare Database #1 and Database #2 below DATABASE #1 POSTS--------------------------------- |___Id________Category_Id______Body__| | 1 "For Sale" "...." | | 2 "Requests" ...
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2answers
122 views

Proper design for models

I have a class called ReplaceRule this is used by 2 classes DocumentRuleViewModel and SectionRuleViewModel as a List<ReplaceRule> in both Question 1: In my database implementation I have 2 ...
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vote
3answers
47 views

Archiving data by semester

The problem is similar to this question, but not a duplicate. What I'm looking for is a better solution than my current one. I'm building a web application for a department in my university, and due ...
1
vote
1answer
62 views

My web app uses a number of photo hosting APIs. What would be an effective database design to store their limitations?

For the sake of an example, let's say I'm using Picasa, Flickr and 500px APIs, and that each of the services has limitations on these simplified parameters: overall account space individual file ...
0
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1answer
42 views

Full data history, current values can be rebuilt ignoring provisional or invalidated changes

I would like to create a website for a local school and then offer it to others. The school's main headache at the moment is capturing student marks and comments at the end of each school term. The ...
5
votes
3answers
395 views

Is it ok to have a class that only has boolean properties?

Scenario We have a class Vehicle, this class contains some properties to define the object such as a CarBrand, TransmissionType, Color, etc.. A car (vehicle) also has options, these days a lot of ...
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0answers
33 views

Creating a new table referencing older one vs just creating a column

I'me developing an iOS chat application and working on the db design for the contacts feature. There are 2 kinds of contacts- Unsaved Contacts - Contacts with who you've conversed with, but not ...
1
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0answers
26 views

Offsetting high usage in a multi-tenant database environment?

I'm writing a research essay over distributed cloud-based systems, and one of the topics that I'm trying to touch on is potential solutions to high database utilization in a single-database multi-...
3
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3answers
173 views

When dealing with tens of billions of rows in a web app table, would a NoSQL database be noticeably faster than a relational one? [closed]

I'm currently designing a conceptual web app, where users can submit posts, comments, and "like"/"dislike" both of those. However, I am not sure of how to store the (dis)likes, because of how many ...
0
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0answers
20 views

Is having a singleton collection in Mongo (i.e. equivalent of an SQL table with one row) an anti-pattern?

I've been looking for ways to implement this, and haven't found it anywhere, so wonder if I'm doing something silly. Essentially I have a set of information which is relevant to the entire database/...
0
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0answers
28 views

Should I use weak entity instead of regular to describe my kind of components?

First time trying to make a E/R model of my database. Trying to understand weak entities and regular entities. Should I make the CPU, RAM, Mainboard, etc. entities weak instead of regular?
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3answers
61 views

What are the theory behind implementing two mirrored HashMaps that can accept write operations? Do I need a broker to mediate conflicting writes?

So imagine two HashMaps that need to be mirrored across two different machines, A and B. Whenever I make a modification to machine A, machine B sees it and vice-versa. Problem is: These two hash maps ...
4
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2answers
61 views

Is it a good idea not to embed certain one-to-one relationships in a Mongo database?

I'm designing a NoSQL database schema - MongoDB in particular - and I'm wondering if it's a good idea not to embed certain one-to-one relationships. For one example, I have an accounts collection, ...
1
vote
1answer
67 views

How many vertices/nodes are too many in a graph and stop being beneficial?

Background I'm working on a project that requires me to keep track of transactions as well as the flow of items in a game. In order to do that, I'm storing those transaction in a graph db (Orient-DB)....
5
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3answers
198 views

Use of booleans in a database

I'm using Visual Studio 2013, .Net 4.5 and SQL Management Studio 2012. I have a table that tracks offices in my database. On the application side there are a some display rules regarding the layout ...
0
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0answers
45 views

Which is the best way to manage multi-account multi-user web application?

I am junior web developer, currently I am developing school application with PHP and MYSQL. After finishing the app I would like to distribute to more schools by allowing them to register in the app ...
3
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5answers
255 views

Is it a bad practice to have a “record status” column in a database table?

I have to clarify first that the status column is not intended to reflect the status of a real-world item represented by the record (row) in the table. Rather, it is intended to show the status of the ...