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

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0
votes
1answer
165 views

Recommendation for a database to query records with attributes that are arrays or hashes?

I'm building site with a very simple data structure: documents that are nodes that reference other nodes that each have arrays of parents, children and siblings, so the structure is: Node: uuid name ...
1
vote
5answers
490 views

Why is it evil to run selects from a prod server?

I'm basically looking for arguments to persuade the internal "consultants" at work as the following are not working: What happens if you do a Cartesian join and crash the server? You don't need to ...
7
votes
5answers
2k views

Is MySQL viable for small-medium business applications

After having worked with a Microsoft stack - VB.Net, ASP.Net, SQL Server - for the past 10 years, we are now faced with having to develop an application for both Windows and Mac environments. It has ...
1
vote
2answers
154 views

Using a column to store the company or a separate database?

I am writing an system for the company to put their promotion material on the site, which is like some kinds of CMS. So, I need a database that store their data, but I am considering how to store ...
3
votes
4answers
244 views

How can I design an application so that it works well with a database selected by the customer?

I want to write an ASP.NET 4.0 application with IBM DB2 Express-C as its back-end. One thing that worries me, is hosting this application on a remote server. I don't know any hosting provider who ...
5
votes
1answer
1k views

Which NoSQL repository is most suitable for a Twitter-type architecture?

In an upcoming project I need to create a Twitter like web application where the basic idea is to read / write short messages and status updates (similar to tweets) and group these messages (just ...
12
votes
5answers
3k views

Indexing a database

I am not so familiar with databases and now I am trying to understand the indexing mechanism. From what I know, in a RDBMS, indexing on a column makes searching by that column faster. This is also ...
1
vote
2answers
276 views

Pro's/Con's to database table layout as it relates to maintenance & extensibility

Basic pseudo class layout below... class Location(): # Class containing information about a location. id address_one class CustomerLocation(Location): customer_id account_rep class ...
3
votes
2answers
181 views

How to do locking and not use a database?

I have a project which involves re-writing pretty much all the back end of a legacy application. It uses XML for persistence and was originally written as a single user system. With one large XML ...
3
votes
3answers
906 views

Unit/Integration Testing my DAL

So I've done some research on this but I couldn't quite come to a conclusion, so I figured I'd ask you guys to see if I could get some other opinions. All of my database access is currently done ...
2
votes
3answers
266 views

Standard semantic name for 3rd table in 3NF

For 3 tables that are in 3NF, a many-to-many relationship, is there a standard name or term to describe the 3rd table, the one that associates the other tables? Basically, I'm looking for a semantic ...
-3
votes
4answers
345 views

I am trying to figure out how difficult or expensive it would be to add this feature

I am trying to figure out how difficult/time consuming it would be to add the following feature: We have a database with our subscribers and we want to send updates to paying subscribers. The catch ...
2
votes
2answers
394 views

Dealing with large amounts of web service requests and storing that data

I have a desktop application that sends a POST request to my website every 5 minutes. This post request can contain a variable amount of data about the PC sending the request, but typically it ...
11
votes
4answers
317 views

Can I use the database structure of an open source project?

I found a database structure for a CMS system and I want to copy it with the EF that this database is done in, is it OK to copy the database structure of open source software which is under GNU v2 ...
4
votes
1answer
354 views

Technique for multiple users on same datasets

This is more a learning question than coding, but I'm certain it's a common issue for anyone developing administration systems or applications in php/mysql/js etc. I've developed quite a complex ...
0
votes
2answers
482 views

How to store personal information properly?

It's not about security or something. There is a table to record user information, like username, password, postcode and so on, one record per person. There is also a table called post to record the ...
2
votes
4answers
292 views

Do paint programs also need database?

I was thinking about how would a paint software works. Firstly I thought that it might not use any database but when I started thinking about the undo function I realized that it might be that the ...
5
votes
2answers
303 views

Immutable design with an ORM: How are sessions managed?

If I were to make a site with a mutable language like C# and use NHibernate, I would normally approach sessions with the idea of making them as create only when needed and dispose at request end. ...
4
votes
2answers
423 views

What are the relative advantages of dictionaries versus databases?

I have an environment that supports both dictionaries (json style) and databases (not relational or anything, just formatted data by row and column). My application doesn't really need database ...
4
votes
3answers
243 views

cost trade-offs for deploying changes to prod, stored procs vs. LINQ

Some context for thisi question: it is not about development time over the entire iteration of development, but just the stage of deploying changes from dev to prod environment. "LINQ" here really ...
3
votes
1answer
159 views

Who's responsible for a master / slave switch?

We are introducing a master / slave replication schema in our web application. At certain scenarios we would prefer to explicitly direct reads to a slave and writes to the master, which to me is an ...
1
vote
3answers
216 views

several similar tables vs several one-to-one relationships?

I have a sort of blog application that I'm working on for constrained writing. The posts have several types, and share some columns in common (title, body for instance), but they also have columns ...
9
votes
4answers
869 views

Benchmarking databases

I see lots of discussions flying around about performance of db 'x' or that moving from 'x' to 'y' improved our site performance. I'm yet to see proper benchmarking that works across different types ...
2
votes
2answers
317 views

Concurrent Data Processing by Multiple People

Let's say I have a page, accessible by several people concurrently, that lists information that must be processed in some way by the user, after which it is either marked as "completed" and ...
0
votes
3answers
365 views

database migration: upgrade schema deployed on client machines

I'm working on an application, which when deployed is installed locally on client machines, and uses a local database server. Stupidly, I didn't plan for schema changes -- and now it needs to change. ...
-3
votes
7answers
391 views

Selling LINQ To Management

I recently started working at a new company that currently doesn't use linq, but does use C# and the .net framework. I'm coming from a LINQ background, so I'm biased, but I still think there are a ...
2
votes
8answers
1k views

Why are SQL databases still used with ORM?

ORMs and persistence ignorance make perfect sense: if I am programming in a language, then I want to use the language's native implementation of objects and data structures to drive my program. I ...
4
votes
1answer
952 views

How can I integrate and store sessions in my database, as opposed to storing them in a cookie and file system?

I've never worked with sessions in a database before, and I'm a little unclear on how they work. I have a user class already designed which stores user information: username, password, email etc. I ...
0
votes
1answer
888 views

What are the important factors for database table design and object design?

When I do database table design, I often wonder if I should try to make the table as simple as possible, or if I should make the object as clear as possible. The requirement is to store all month of ...
1
vote
5answers
457 views

Database design good practices [closed]

I recently joined a new position as SW developer and during the interview process everyone stressed the importance and the pride of the quality standards of the firm in each and every process they ...
4
votes
1answer
633 views

Which questions a Software Developer/Sr. Software Developer (non-DBA, non-Database Enigneer) should be able to answer about databases? [closed]

I am a Java developer and most of my experience is on Java. But sometimes I have face some database related questions in the interviews. Hence I wanted to ask that from the interview point of view, ...
2
votes
1answer
615 views

Querying key/value store

I don't know whether this question is reasonably answerable (and therefore will be closed), but I will take my chances: What are the possible problems (and solutions), one might encounter, when ...
1
vote
2answers
93 views

Possibility Program for number of pieces

I would like to put a program together to calculate the number of 60' pieces would be needed from a list of shorter pieces. For example, I sell rebar cut to length from our standard length of 60'-0". ...
10
votes
5answers
2k views

Is there any reason to use VARCHAR sizes rounded to a 128/256/4096 byte offset?

In database schema's, I often notice VARCHAR sizes are rounded to the byte offsets 128/256 or 4096. I've done it before as well, and the idea behind it was probably something with efficiency. ...
2
votes
1answer
272 views

Programming logic to group a users activities like Facebook

So I am trying to develop an activity feed for my site. Basically If I UNION a bunch of activities into a feed I would end up with something like the following. Chris is now friends with Mark ...
29
votes
8answers
15k views

Create my own database system [closed]

I need to learn how databases work in order to use them more efficiently, and my way of learning is by doing. I want to create my own database system. I am not referring to creating a pseudo-database ...
4
votes
7answers
1k views

How to develop complex applications

I want to know the approach in developing big complex application regardless of which programming language to use. I want to know how developers make such big applications such as internet banking, ...
1
vote
2answers
401 views

Database design

I'm on the way developing an application which requires a kind of dynamic database, So this is what I want, This is the for reading the details of a class, the number of variables and methods ...
0
votes
2answers
1k views

What are the pros and cons of storing files in DB2 vs folders? [duplicate]

I work in a Web Application where users are allowed to upload files. They can retrieve and view those files at a later point in time. A solution that user works with can have multiple attachments but ...
2
votes
3answers
229 views

How should we deal with multiple transaction-report requests?

We are developing a system for the retail market and of its features will enable clients (actually consumer clubs) to go through all transactions made by end-clients. One of the ways to get this ...
2
votes
1answer
132 views

Big table with referential integrity or field typification?

I'm using an ORM (Propel) and PHP to create Objects and store them in a database. So, I'm facing a recurrent problem and I'm pretty sure this happened to someone before. My data model looks something ...
6
votes
2answers
4k views

What's the difference between MariaDB and MySQL?

What's the difference between MariaDB and MySQL? I'm not very familiar with both. I'm primarily a front end developer for the most part. Are they syntactically similar? Where do these two query ...
3
votes
4answers
1k views

Recommend Stanford Online Database Class?

I am taking the Stanford Online Machine Learning class which is outstanding. http://ml-class.org Is anyone taking the Stanford Online Database class: http://www.db-class.org? Does it seem useful if ...
9
votes
5answers
13k views

How to quickly search through a very large list of strings / records on a database

I have the following problem: I have a database containing more than 2 million records. Each record has a string field X and I want to display a list of records for which field X contains a certain ...
0
votes
3answers
1k views

What are the dangers of setting an unlimited database transaction life timeout?

We have a process that may last between a few seconds and a few minutes. As such, we may update just a few records or thousands of them. The process can be committed only when everything has been done ...
15
votes
7answers
1k views

Does it make sense to standardize including a created date and last updated date field on all DB tables?

My boss is currently attempting to apply some development standards to our team, so we had a meeting yesterday to discuss the standards which was mostly going well until she brought up: All DB ...
3
votes
5answers
749 views

Good techniques to speed up database execution

I have an ASP.Net application that is using a MySQL database. My queries are not executing as fast as I would like them too. Are there some standard ways to increase the speed of a MySQL database ...
3
votes
1answer
1k views

How to store a simple DB “in the cloud”?

Even though the name is similar my question is not a dupe of the very fine question here: Database in the cloud? I've got a webserver (Java/Tomcat) running a webapp (which I wrote) on a dedicated ...
4
votes
4answers
714 views

How to add image support to client-server database application?

I have an architectural question about a project that I am working on. Currently it is a simple .NET C# application that runs on several client machines, and communicates with a central MySQL server ...
3
votes
3answers
3k views

How to design a database wherein multiple tags(string) are to be associated with an id?

I have to design a database wherein I have to associate an audio_id with multiple tags(words). I am considering following approaches to select one from these: 1) To have multiple fields for multiple ...