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

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1
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1answer
59 views

What should the payload of a “domain event” generated through “change data capture” include?

Using domain driven design and event sourcing ... Given I have a table of 3 columns: (A, B, C) with an existing row of data: (1, 2, 3), when I update the row to contain values (1000, 2, 3) and I run ...
0
votes
3answers
112 views

Website testable design [duplicate]

I have developed two web services. The main service is a RESTful service (using DB), and another UI service that uses the RESTful service. Say I want to test the UI for now (integration tests), every ...
44
votes
13answers
4k views

Is it necessary to create a database with as few tables as possible

Should we create a database structure with a minimum number of tables? Should it be designed in a way that everything stays in one place or is it okay to have more tables? Will it in anyway affect ...
1
vote
1answer
94 views

Database choice [closed]

I am working on a system where I am replacing and existing Cobol system with C#. For the database I have hit some requirement which I am having a hard time to find complete support for (tried SQLite ...
1
vote
1answer
93 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 ...
3
votes
3answers
217 views

Is there a 'standard' SQL that can replace all the various custom versions?

I have been writing SQL for over 10 years now. I am extremely proficient at it and have experience working in SQL Server, Oracle, MySQL, PostgreSQL, etc. While there are multiple standards out there, ...
6
votes
4answers
5k views

Handling database schema changes when pushing new versions

During times of heavy development, the database schema changes both rapidly and continuously, and by the time our weekly push to the beta build comes around, the schema has changed so much that the ...
15
votes
4answers
4k views

Databases: Where should the application logic run? [duplicate]

http://highscalability.com/blog/2010/11/9/facebook-uses-non-stored-procedures-to-update-social-graphs.html talks about how Facebook moved logic out of the database into the application in order to ...
1
vote
2answers
113 views

When should I implement authentication in a database?

I'm currently embarking on a MongoDB project (a simple user login system), and I notice that there is an option for authentication. Here is the server string, with the userinfo shown as optional ...
0
votes
0answers
34 views

How can I aggregate data from separated databases in more efficient way?

Firstm I'm using PostgreSQL 9.3. I'm solving the problem which is to retrieve a data from a separated databases and to render it into a web page. The web project is on the Java (JSF 1.2). Presently ...
-3
votes
1answer
99 views

How can I test a method which aggregates data from a database? [closed]

I'm developing the web Java application and come across the following issue: I'm using jUnit 4.5. Suppose that I have a method which aggregates data from a database for the rendering their to a ...
0
votes
2answers
80 views

Are the concept of database driven website and the CMS made website same?

I'm having little difficult time of understanding the few logics of web development. Should I call home page, about page (or any other pages of a website whose contents change very rarely and no ...
0
votes
6answers
123 views

Should I rebuild my read only database every time I launch my server?

I'm getting into web development, and I'm trying to get a grip on databases. In an app I want to make, there is a read only database that will be filled up with a large amount of data, which will be ...
0
votes
0answers
206 views

Evaluating local storage for data persistence for small, stand-alone applications

TL;DR - I have a standalone application that will remain relatively small. I'm trying to evaluate between using XML files or a lightweight database for local storage of data that needs to be ...
3
votes
1answer
153 views

End user query syntax?

I'm making a command line tool that allows end users to query a statically-schemed database; however, I want users to be able to specify boolean matchers in their query (effectively things like "get ...
0
votes
1answer
69 views

How to implement a Daily Recap email of Database records modified the previous day sent to Subscribed Users like Basecamp does?

I am building a Project Management module for SugarCRM. It consists of a "Project" which has information on the project like Name, description, start and completion dates, creator name, status ...
4
votes
3answers
341 views

database design, how to handle freelancers

The context i'm modeling a database for a small ERP system. However I've recently hit a difficult spot that I'm having a hard time wrapping my head around. The logic of it involves a few special ...
1
vote
1answer
135 views

Are CRUD operations intended to be used with collections?

CRUD operations, by definition are... interfaces that permit users to create, remove, modify or retrieve data Implementations of CRUD interfaces can come in various shapes and sometimes they are ...
0
votes
1answer
132 views

Real time middleware system: Direct DB access vs REST API access

I'm developing a complex environment which involves a web application, a mobile app and a real time middleware system which accesses the DB for on-site tag readings. Currently, the web application ...
13
votes
6answers
8k views

Is there any reason to use varchar over text columns in a database?

Is varchar just a remnant from before text came around, or are there use cases where you would want to use a varchar? (Or char for that matter..) (I use Postgres and MySQL (MyISAM) daily, so those ...
7
votes
5answers
5k views

What is needed to deploy an application that uses Microsofts new LocalDB?

I'd like to know what microsoft components need to be installed for this new LocalDB to run on a users machine. Now in CTP3: SQL Server Express LocalDB LocalDB is a new lightweight deployment ...
0
votes
2answers
179 views

Is a mocking framework useful if I'm unit testing a repository/database? [duplicate]

I'm trying to improve my testing skills. I frequently hear about mocking framework to build fake objects (as far as I understand). Right now I need to test my repository (the usual add, remove, update ...
3
votes
2answers
165 views

Is a bad practice create database structure on the runtime?

Im creating a crawler app that will always in the beggining, when the Class constructor, ensure that the basic database structure exists. Is this a bad practice? What is the advantage os creating the ...
0
votes
2answers
128 views

Is it a bad practice to keep database schema scripts (DDL) and manipulation (DML) scripts in different modules

we have a project structure like the following "module-shared" module depends on "module-database" module and some other modules depend on "module-shared" but no other module depends on ...
2
votes
2answers
102 views

Unit test database insert/remove and atomicity

I create my compact test database. This is a SDF file, embedded as a visual studio resource. When test suite starts this database is copied in %LOCALAPPDATA% so my test can use it. The first method ...
5
votes
4answers
2k views

What's stopping Oracle from supporting identity (auto-numeric) columns? [closed]

EDIT: As gavenkoa's answer points out, Oracle Database 12c (released a couple of years after this question was asked) has support for Identity Columns. As far as I know, Oracle's RDBMS is one of ...
7
votes
6answers
344 views

How best to handle database refactoring within a team?

We are currently usign a roll-forward approach to DB changes, akin to Migrations, where each developer creates and checks in a script that promotes the latest version of the DB to a new state. ...
0
votes
0answers
34 views

Storing last polled database timestamp unix

I have a Unix script which is called by a scheduler (CTRL M) every 3 seconds. The script queries an external database(not belonging to my application and therefore I can only query it) to check for ...
0
votes
1answer
136 views

Are there two type of associations between objects or are there just different representations?

I've been spending some time on 're-tuning' some of my OOP understanding, and I've come up against a concept that is confusing me. Lets say I have two objects. A user object and an account object. ...
4
votes
7answers
323 views

Are mutliple database calls really significant with a network call for a web API?

At one of my employers, we worked on a REST (but it also applies to SOAP) API. The client, which is the application UI, would make calls over the web (LAN in typical production deployments) to the ...
6
votes
3answers
333 views

Proper Response to HTTP Request When Too Much Data is Requested

I'm building an API for an ad serving platform that will allow you to request tracker data for ad campaigns. Campaigns often exceed hundreds of millions of requests, which means there will be many ...
1
vote
1answer
125 views

Automatic denormalization for a NoSQL database application

We have a use case where we store table-like data, but we know about the schema of the data only at runtime. In our application, a power user defines a schema and normal user can create records and ...
1
vote
5answers
168 views

Database design with performance issue and use of views

I am designing database for a school system. I am having to create a lot of tables and a lot of link tables to maintain a structure in the system. I am trying to maintain foreign integrity and trying ...
1
vote
1answer
96 views

How to save appointments in database?

There are 2 entities. One is admin. The task of admin is to define slots for appointments which will be taken by applicants. The admin will choose a default time for the appointments like 10am to ...
3
votes
2answers
151 views

Whether to store all numbers or just their ranges in database for this application

I'm developing a (PHP MySQL) Web App which will sell dynamically generated real time cell phone numbers for cellular companies. A company will ask for, say, a thousand numbers and this app will check ...
0
votes
1answer
38 views

Tweaking a ranking algorithm from a few variables

I'm going to have a mySQL table with elements in it and would like to rank them in the same manner than Reddit but not quite. I'd like to know how to add or remove importance to a variable in my ...
0
votes
1answer
103 views

Efficiency of getters/setters with database performance

I'm currently in the process of refactoring a very old personal project of mine, which used procedural PHP-in-HTML code. I'm modernising it as a learning project, using OOP where beneficial. I ...
0
votes
0answers
45 views

Database conceptual Question [duplicate]

When querying in database through PHP, is it good to open mysql connection before every query and close it as the query completes? or should we open the mysql connection as soon as the first query ...
7
votes
3answers
316 views

Does it make sense to develop open source python library for database inspection? [closed]

Some time ago I came up with an idea for a library for database inspection. I started developing it and got some very basic functionality, just to check if that's possible. Recently however, I get ...
-1
votes
2answers
107 views

Loading database in memory vs querying

I am currently developing a continuous backup software. The key feature of the software is instant backup meaning that each time a file is created, modified, renamed or deleted the change is ...
0
votes
2answers
102 views

Minimal set of critical database operations [closed]

In designing the data layer code for an application, I'm trying to determine if there is a minimal set of database operations (both single and combined) that are essential for proper application ...
3
votes
6answers
484 views

How to define a natural id in database?

There are a lot of manuals. I am trying to create an database to hold information of these documents. But, there is a small problem. How can I give meaningful id to the manuals? Are there any ...
3
votes
2answers
89 views

An algorithm for finding subset matching criteria?

I recently came up with a problem which I would like to share some thoughts about with someone on this forum. This relates to finding a subset. In reality it is more complicated, but I tried to ...
2
votes
1answer
97 views

Finding a way to simplify complex queries on legacy application

I am working with an existing application built on Rails 3.1/MySql with much of the work taking place in a JavaScript interface, although the actual platforms are not tremendously relevant here, ...
2
votes
1answer
104 views

Using json as database with EF, how can I link EF and the json file during DbContext initialization?

For a personal testing-project I am considering to create a SPA with the following technologies: ASP.NET MVC + EF + WebAPI + AngularJS. The project will make use of small amount of data, so I was ...
2
votes
2answers
155 views

One codebase - lots of hosted services (similar to a basecamp style service) - planning structure

We have built a service (PHP Based) for a client, and are now looking to offer it to other clients as a hosted service. For this example, think of it like a hosted forum service, where a client signs ...
0
votes
1answer
90 views

Prepared statement alternatives for this middle-man program?

I have an program that is using a prepared statement to connect and write to a database working nicely, and now need to create a middle-man program to insert between this program and the database. ...
1
vote
1answer
107 views

Where to store front-end data for “object calculator”

I recently have completed a language library that acts as a giant filter for food items, and flows a bit like this :Products -> Recipes -> MenuItems -> Meals and finally, upon submission, ...
-2
votes
1answer
65 views

How to get a database on my filesystem that I can use in my application [closed]

I'm making a .NET application where I'll have a lot of data entries. This will not go to any server though, but needs to be stored and updated, frequently on the local machine. I would like something ...
0
votes
1answer
77 views

Dealing with data, when your database is under version control

Currently my database is not under some kind of vcs, we can get deltas but that's about it. I would like to try and make product deployments more automated, and less time consuming. I understand that ...