database

Which is beneficial for start up; Linq to SQL or Nhibernate?

I want to learn ORM and I wonder which is beneficial for start up; Linq to SQL or Nhibernate. considering time,adaptation... etc ...

How do I make a database backup and have it stored locally?

So here's the challenge. I need to use C# to back up a database locally from a remote database server and the only share we have is \\computer\c$. If the answer is to back up to a location on the remote database server and then copy that local, assume there is not a share on the remote location. Just b/c I have access to the database d...

What is a good option for a Non-Blocking "Database" (Using a TCP Socket Server)

In short I'm creating a socket server so I can add multiplayer support to my Flash game (Using Actionscript 3.0 Binary Socket on the Client-End). I decided to go with Python since I'm the sole developer of the game/server and this will be my first non-blocking socket server. I was going to use Twisted but I deiced that I would use Pyth...

Using mySQL on Tomcat server?

Hi all, I have the following problem at the moment. I am using mySQL and Tomcat for my college project, and I am able to connect mySQL DB locally from a jsp page. However, if I try to use mySQL and server in my college, I got the following error Exception: Communications link failure. The last packet sent successfully to the server was ...

Deleting files and corresponding entries from database

I have a web site which handles files management. User can upload file, add description, edit and delete. What are the best practices for that kind of scenario? I store files in the file system. How should I handle deleting of the file? In this case I have to entities to delete: file and entry in database. First scenario is that I de...

Postgres Alter Column Integer to Boolean

I've a field that is INTEGER NOT NULL DEFAULT 0 and I need to change that to bool. This is what I am using: ALTER TABLE mytabe ALTER mycolumn TYPE bool USING CASE WHEN 0 THEN FALSE ELSE TRUE END; But I am getting: ERROR: argument of CASE/WHEN must be type boolean, not type integer ********** Error ***...

Why don't databases intelligently create the indexes they need?

I just heard that you should create an index on any column you're joining or querying on. If the criterion is this simple, why can't databases automatically create the indexes they need? ...

How do I add a unique key to a column in MYSQL?

If I want one column to be unique, or two, or three? ...

Inserting new columns in the middle of a table?

When one uses "ALTER TABLE tab ADD col", the new column gets added to the end of the table. For example: TABLE: TAB COL_1 COL_2 COL_4 ALTER TABLE TAB ADD COL_3 table will become TABLE: TAB COL_1 COL_2 COL_4 COL_3 However as the naming of my example columns suggests I'd actually like the table to end up like this: TABLE: TAB COL_1...

What is the best approach to writing a stored procedure for a 1:N relationship performing an insert?

If I have two tables A and B: A(AId, a1, a2) B(BId, AId, b1, b2, b3) On first thought , I wanted to write a sp (stored procedure) incorporates the two insert statements. But, on a second I thought I felt it would be nicer if I had a separated sp to do an insert for the table B and another to do an insert for table A while calling the ...

Fix ORA-02273: this unique/primary key is referenced by some foreign keys

Trying to drop a unique constraint I've got such error: ORA-02273: this unique/primary key is referenced by some foreign keys How to find the list of foreign keys by which my unique constraint is referenced? ...

Implementing rental store in Rails: how to track an inventory state over time?

Let's say you're implementing rails app for a snowboard rental store. A given snowboard can be in one of 3 states: away for maintenance available at store X on loan to customer Y The company needs to be able to view a rental history for a particular snowboard a particular customer The rental history needs to include temporal dat...

Hibernate - changing connection string during runtime

I have JSF + Hibernate app. During runtime, i need to change database, to which user is connected. For example, User can manually switch databases in my app, so app is connected to the chosen one. I read about Hibernate Connection Provider. Can it help me? ...

Need help debugging a custom authentication plugin for Moodle

I'm trying to authenticate against the user db of my website (CMS based) and it uses a slightly different approach at storing hashed passwords. It uses a randomly generated salt for each user. The salt is stored in the user db along with the hashed passwords. Hence, direct field-mapped authentication (as the External DB plugin does) won'...

How to implement multi-level hierarchies in user management

Implement multi-level hierarchies so that super user have also all rights that sub user have means super user can also manage sub-users jobs. How design the database for this. ...

How can i write stored procedures in my application using SqlHelper?

I'm looking at my options here. I would love to know how to write my stored procedures not in the SqlServer but in my app (DB Layer) using SqlHelper? Can anyone help? ...

Internationalization on database level

Could anyone point me to some patterns addressing internationalization on the database level tasks? The simplest way would be to add a text column for every language for every text column, but that is somehow smelly - really i want to have ability to add supported languages dynamically. The solution i'm coming to is one main language ...

HTML checkbox change value in MySQL

I have a checkbox and I need that when it is "checked" to alter a MySQL Table value to "yes" and if it's checked when you uncheck to "no". I want to accomplish this with Ajax. How can this be done? ...

generate web based database front end

I've created a database schema for an internal (CRM like, ~15 tables) application. I would like to "convert" this schema to a usable web application. All details (foreign key, ordinality etc) can be extracted from the schema so I'm looking for a tool that will generate all CRUD code (that can be hosted on a Linux server). Any suggestions...

Flash charts that can map/dither the data on X axis

I looked at different flash chart software (free and commercial) and could find only one that supports the feature I want: map my dataset on the predefined X axis. Let me give an example. Let's say my X axis is time. The time is represented in hours. So let's assume my X axis has last 24 hours. Now the data I have in the database contai...