This tag is for general database questions; if you question is specific to SQL use that tag instead.

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-1
votes
0answers
9 views

Delphi XE with Firebird Database, Datasnap Driver, DataSnap Service vs other schemas when working with mobile apps [on hold]

I`ve found out that most of the time it is recommended to use this schema when connecting to a localhost server. Not necessarily Firebird as Database, but the Driver and the Service are always ...
-2
votes
0answers
30 views

Reducing the text database for using in android apps [on hold]

I have a text (UTF8) data that should be used in android (ebook like) app. How I should convert this text data (>20MB) to some other type of data that have minimum size on memory and can be used in ...
0
votes
0answers
30 views

What could possibly be a Mysql database structure for an web app say like Flurry?

Simply say, I'm working on a web App say like Flurry (http://www.flurry.com/), that would communicate with a Smartphone App trough API. Right now I'm designing the database structure, and I guess ...
0
votes
0answers
36 views

Category tree, is it worth it?

I need some insight on how to design my database regarding categories. My site allows the users to post several different types of things for example, recipes, articles, products etc and there will ...
2
votes
3answers
80 views

Is it an abuse of SOA to use it as a database abstraction layer?

I have a question whether it is a good or bad practice to use an SOA layer for the application servers to talk to the database. A web application server can obviously directly connect to a database, ...
2
votes
1answer
78 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 ...
-1
votes
0answers
13 views

How BeanPropertyRowMapper works internally in spring?

I know that BeanPropertyRowmapper use setter method when I fire select query but is it uses getter method too or not ? I don't want to make my custom row mapper or hibernate or JPA. I have face below ...
1
vote
3answers
120 views

How to choose DB and/or DBMS for own application? [closed]

I'm creating application in C++ and found out that storing information in XML file was very prodigally. Despite the possibility to read it without any specific application, random access via DOM or ...
0
votes
1answer
24 views

Large volume report operations, how best to replicate transactional data

We are overhauling a legacy accounting app that has some large reports. One concern that has been raised is due to the transactional nature of the data, if we start a long running report how do we ...
0
votes
1answer
50 views

Closed source proprietary web application with an AGPL source code in iframe or sub-domain [closed]

In a closed source proprietary web application, if I use an AGPL product in a sub-domain or in an iframe do I have to open-source my project? If answer is no, is it possible that both applications ...
3
votes
2answers
163 views

Meaning of an “instance of a database”

From http://en.wikipedia.org/wiki/Extension_(semantics)#Computer_science In computer science, some database textbooks use the term 'intension' to refer to the schema of a database, and 'extension' ...
0
votes
0answers
37 views

Minimizing database requests for moves of a chess game?

I'm writing a webapp for chess which, for a given move and a database of games, shows all the moves that follow from that move. Pretty much what this website has already done: ...
-3
votes
0answers
15 views

Receive MMS Picture Message to hosted database [closed]

I've been reading up a lot on receiving messages from the phone to a server. I've successfully been able to receive SMS messages (Simple Text messages) but I am in the need of trying to receive MMS ...
1
vote
1answer
26 views

RavenDb - Get data through a REST Web API

I would like to build a RESTful API where I need to get data from a RavenHQ-cloud-database. First of all, is this possible? The idea is to have multiple applications (xamarin-app, mvc-app, etc.) and ...
0
votes
2answers
99 views

Saving to file before storing into a database in a REST service

A mobile back-end I am building should receive a larger amount of data (some sensor recordings) from an Android phone. The phone does not have much use of it so it was most efficient to store the data ...
1
vote
2answers
44 views

S3 image urls in database

I have an application where users will be able to upload multiple images for one Product. I'm planning on using jQuery File Upload, and Amazon S3. The thing I'm confused about, is how people usually ...
1
vote
2answers
88 views

Users in SQL databases

I took up programming a couple of months ago (alongside my day job) and am struggling with a couple of basic concepts. Currently, I'm trying to learn how to build a database based PHP login/logout for ...
5
votes
1answer
132 views

How to efficiently store big time series data?

I need to store and to be able to query some very large amounts time series data. Properties of the data are as follows: number of series : around 12.000 (twelve thousand) number of data points, ...
1
vote
4answers
112 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 ...
4
votes
2answers
79 views

best way to attach database structure for an open source project

I have a small project which I want to publish on github. The problem is that my project contains a database. I don't know what is the best way to attach the database structure. I may get the create ...
0
votes
1answer
31 views

Quickly write log entries from http requests in a MySQL database with high performance

When a dataset is saved in the software I use, a http request is triggered (fire-and-forget). Information like the timestamp, the user and the changes made are listed in the GET parameters. Now I ...
1
vote
1answer
129 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
64 views

Database vs. server-sided scripting language [duplicate]

To keep my question short and to the point, consider this: $relation = $mysql->query("SELECT relation($loggeduser, $requesteduser) AS a")->fetch_assoc()['a']; if ($relation != BLOCKED) { ...
1
vote
1answer
92 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 = {}; ...
1
vote
2answers
76 views

Retry method for generating unique code

In an app, a user can initiate the generation a six-digit alphanumeric code (actually done via Web API). The code needs to be checked against a remote database to ensure it is unique. Other than for ...
5
votes
1answer
189 views

Log to file or to database table?

I'm developing a web application which uses MS SQL for various data: including users, user accounts, user licenses, license prices, invoices. I need to log users' real-time usage of the system, and ...
7
votes
3answers
189 views

How to model and store an entity which has “one or more” values

I'll use C# to design the model to be persisted Let's suppose I have the following entity: public class Episode { public int Id { get; set; } public string Title { get; set; } public ...
1
vote
1answer
72 views

More than 20 Records Inserted in a Span of 1 Sec

Well, this is not specific to any programming languages. I came across this situation in Android, iOS, PHP and .NET. The problem is many times I come across a situation while building IoT apps, where ...
0
votes
1answer
107 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
votes
1answer
151 views

Matching algorithms in context of data quality problems

I work for an organization that has lots of databases containing person information. The data quality is poor. One case was a surname I found like this (this is the worst-case scenario): Mark ...
2
votes
3answers
132 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 ...
0
votes
1answer
131 views

Designing a scalable schema for college database [closed]

I am trying to build back end for college ERP system. The system will be based on LAMP. These is the scenario: Colleges have 5 branches There are 4-6 classes in each branch. There are 80 students ...
0
votes
1answer
28 views

online database with partial access for clients

I'm trying to come up with an online database that my clients would have partial access to. This is for an artwork storage company. We have about 40 clients and would like each to have access to their ...
1
vote
1answer
62 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
votes
2answers
105 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 ...
0
votes
1answer
58 views

How can I iterate over two loops of mismatched sizes, keeping them in sync?

I have a database table in which each row is one movie (with fields like 'title', 'director' and 'writer'), and a related table where each row is one screenshot from a movie (with the fields ...
3
votes
0answers
93 views

Why there is a drop of interest in DBMSs? [closed]

I was playing around with google trends explorer when I tried to compare three major DBMSs: MySQL, Oracle and MS SQL Server. As you can see there is a drop in the interest in these database ...
2
votes
1answer
97 views

Multiple websites and applications using one user database

I've got several applications and websites that will be built around one main application. In a perfect situation users will be able to register once and be able to log into the different applications ...
2
votes
2answers
204 views

architecture of database heavy application

A program I'm currently designing is extremely database heavy, almost anything the user does will alter the database, or read from it. Now I have one interface which defines all these operations, and ...
4
votes
3answers
117 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 ...
4
votes
4answers
228 views

How to prevent race conditions in a web application?

Consider an e-commerce site, where Alice and Bob are both editing the product listings. Alice is improving descriptions, while Bob is updating prices. They start editing the Acme Wonder Widget at the ...
3
votes
2answers
210 views

Why Do B+ Trees Have a Minimum Occupancy of 50%?

As far as I can tell, the basic operations (add, delete, search) on a B+ Tree would function the same if minimum occupancy was 1, or 1/3, or any other function on node size. All the sources available ...
0
votes
1answer
139 views

calculating the average of a value over a month [closed]

I am working on a project right now that is having me calculate monthly interest on a bank account. The way the interest is supposed to be calculated is as follows: Use the daily average to calculate ...
0
votes
0answers
58 views

Entity Framework Lookup Tables

I am coming from working with ADO.net DataSets and feel fairly comfortable with how they work. Mainly, I usually have a DATA table with a large number of REF tables for lookups. In DataSets it was ...
0
votes
0answers
56 views

Syncing structured data and files in Android App with an ORM?

I am developing an Android App which I have developed for iOS before. The app requires that structured data and files are synced across android devices. In iOS, I was using Core Data and synced to ...
2
votes
2answers
40 views

Bulk update in client-server application

Sometimes when coding a client-server application, the client needs to make a bulk update. For example: "mark all pending orders as dispatched". To implement these I typically write specific ...
0
votes
0answers
10 views

compare different approachs for saving related records whose values may change

On a web application for accounting services, I have the good old Invoice. To keep this example as simple as possible, each Invoice has many rows, and each row has its item with its price. At the ...
2
votes
1answer
72 views

Managing Database version controlled migrations using a list/table

I'm not much of an expert in the area but I am aware that solutions already exist to managing database migrations in version control, e.g. sqitch and liquibase. However I'm currently planning a small ...
0
votes
0answers
53 views

Automatically verifying INSERTs when building a PHP(5.3.3) application

I am building a form in PHP. I would like to automatically verify that INSERT queries are successful, and populate data correctly, as opposed to running queries in Workbench or MySQL with every code ...
1
vote
1answer
40 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 ...