Tagged Questions

4
votes
2answers
211 views

Should I use a relational datamodel or Cassandra with ColumnFamily based indexes?

Currently we are working on some storage problems for log data from various servers and communication message logs (HTTP(S), XMPP). There will be many write operations and for read operations we will ...
2
votes
1answer
162 views

How should I implement Transaction database EJB 3.0

In the CustomerTransactions entity, I have the following field to record what the customer bought: @ManyToMany private List<Item> listOfItemsBought; When I think more about this field, ...
5
votes
2answers
173 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, ...
-2
votes
1answer
80 views

Adding a forum to an existing site

I've got a site with ~500 registered members, 300 of which are what you'd call "active". Site data is kept in a MySQL dbase. I'd like to add a myBB forum to the site, but this question applies to any ...
1
vote
4answers
152 views

What are some good tips for a developer trying to design a scalable MySQL database?

As the question states, I am a developer, not a DBA. I have experience with designing good ER schemas and am fairly knowledgeable about normalization and good schema design. I have also worked with ...
2
votes
9answers
1k views

Is there a large bank using Mysql or PostgreSQL? [closed]

I always thought the largest scale of banks use Oracle. However, there is no proof they really use Oracle instead of Mysql or PostgreSQL, nobody knows the secret. Any idea what they really use? Can ...
1
vote
2answers
83 views

In which format should I sent the values in database in PHP?

I am developing an application which is based on the quiz contest for competetive exams. The user can give different categories of tests, which will contain different types of questions of following ...
1
vote
1answer
103 views

Is using dynamically generated code as cache a good idea?

I have a web search interface that can compare products in a table. This data set changes a few times a week. I have been storing a "DISTINCT" list (used for parametric selection) in a cache table. ...
1
vote
2answers
175 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 ...
2
votes
5answers
386 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 ...
5
votes
2answers
127 views

Storing stop/start points in a database

Let's say I am storing start and stop points per user into a database table. For example... let's say in a chat system, a user only needs to see lines 24-293, and 500-512. (Let's say he logged off ...
5
votes
1answer
326 views

Search multiple tables

I have developed a web application that is used mainly for archiving all sorts of textual material (documents, references to articles, books, magazines etc.). There can be any given number of archive ...
6
votes
1answer
164 views

What is the difference between collation and character set?

I have a general question about databases. We usually use the term collation with databases. I would like to know how its different from character set. I guess collation is a subset of character set. ...
3
votes
2answers
499 views

how facebook calculates mutual friends?

In your opinion, how facebook calculates mutual friends? Has it cached all mutual friends for each user? Let MySQL calculate through a query? Makes a query to the database and then it calculates the ...
4
votes
7answers
479 views

Best practices to follow with database indexes

What are some DOs and DONTs for improving database performance using index? A DO would be a case in which an index should be created, or another indexes related tip that will improve performance. A ...