Suppose i have made a single user program that receives its data from a database on a SQL server. What things do I have to change to the program to make it a multi user program while preserving data integrity?
View 3 RepliesI am designing a fairly small application to manage a waiting area for a clinical department. There will be a receptionist who books appointments and updates exisiting appointments to say that a patient has "Arrived". In seperate rooms will be nurses who call patients who have "Arrived" and update the appointment as "In Session" and finally as "Discharged". The appointments are viewed in a flexgrid with nurses across the top and time down the left, patient names are displayed at the relevant times and the cells are shaded a colour to represent the current appointment status ("Booked", "Arrived", "In Session" and "Discharged").
I am using SQL Server as the back-end and Visual Basic 6 (I know) as my front-end.I have been told that there will be 2 or 3 nurses plus the receptionist logged in to the system but I would like to cater for growth.My question is what is the best mechanism to use in order to reflect the status change made by one user on the screens of the other users currently logged in?
I have been thinking about using a timer to refresh the data at a set interval but I do not want to keep hitting the server excessively (although what is considered excessive? we would be talking about a call for data every 60 secs per user). Plus the server could be serving data for many other applications so this is another consideration.Alternatively I have been thinking about sending some kind of message via Winsock to the other users notifying them of data changes as they happen. I don't have a lot of experience with this and am concerned about clients not receiving messages and users seeing old data. It also seems strange to me that once the days appointments have been retrieved from the database that "in theory" a client could go the whole day without having to query the database again to pick up changes - kind of scary.Some information on the data:We would probably be looking at around 100 appointments per day We capture patient name, date of birth, date and time of appointment and appointment status.What is the standard approach / best practice for this kind of scenario?
I have a system where I would like to show a warning to a user if there try and edit a record that is currently been edited. If this is the case the user will not be able to save the record but only view it.I have an idea of using some kind of class to monitor the activity of records been edited etc but this seams a little over kill. My other concern is that what if the browser crashes or there shut their computer down on how this will effect the state of the page.
Another thought was to use last updated time stamp but this also looks a no go because the way records are been updated? how I could implement something like this. No code is necessary.based on the comments I have added these additional details.database is SQL server 2008 asp.net 3.5 one record could be many parts of the database for instance, the booking table session table and a row in the interrupter table.the user will look at a list of sessions that need booking select a booking and fill out a booking form to make the booking. Want to stop is someone else trying to do the same booking at the same time or while someone else is doing the booking.
I have finished coding a VB.Net application that has connection to SQL Express 2008 database. My question is, what steps do I have to take to make this a multi user application.
FYI:There are 3 tables in the database of which two tables contain data to be viewed by the user and one table is to insert records by the user. The former two tables will be edited by the administrator only. So there is no issue of concurrency. But the one table that is used to insert records by all users has to be dealt with.
I am new to programming. I know how to create simple windows app using VB and Sql Server/AccessDB. My question is this: Can my windows app be ran on a LAN or do I have to create a special multi-user app for a LAN? If the answer is yes, can someone please guide me on how to create a LAN/Multi-user app.
View 2 RepliesI am planning to make a multi-user chatroom client. I have got a web hosting, but I don't have the server. I want to know how to create the chatroom from my webhost and what type of method that I would need to connect it?
View 3 RepliesI need to create a multi user VB.Net application that connects to Access 2007 and has 2 forms. How do I go about it? Please give me a start up.
View 6 Repliesi need an app that can download a table from the db, and when he click a button, i want to update the db with his "offline copy".
Problem is When i use DataAdapter.Update, it doesn't update all the rows. Now this is a problem, because even if his "offline copy" thinks that row 1 is "unedited", some other user may have edited row 1. so regardless of row state, i need to so called "replace" the entire "offline copy" with the database when the user clicks the button in a "last click overrides all" situation
How do I make a multi user database?
Give me the logic, how do I achieve it?
For example, what file should the database be, where should I put the database(I prefer on my server), how do I encrypt the database.
Can I make it in columns? Username column and password column? My application then finds if any username match to the username inputted by user in my UsernameTextbox.Text then see if the inputted username and the password from PasswordTextBox.Text matches.
For now I'm using the If statement for both username and password. I have to write the same code again again for new users.
I want to about a multiuser application that have a server and 2 or 5 client to interect with mssql thorough application. how multiple cleint connect to database in same time.
View 4 Replies[URL].. Unfortunately that is for i think it was 2003. Most likely it wont update and still work. along with that would it be possible to have users be able to private messege each other, create their own user rooms, and add admin features such as kick, ban, look up ip and such?[URL].. as my login system. its been modified so that the connection string wasnt hard coded.
View 1 RepliesI have been trying for years making a network app.I need linked to a video or something, mainly on msdn or some microsoft site, because youtube created videos for coding aren't all that helpful as most of the microsoft made videos.
I need not linked to things like multi-user tcp chat application, as i have looked at these, and even found no code solution, but the no code doesn't allow too much customization and hard to deal with data received to make your own commands send and receive and have events for them.
The multi-user tcp chat application, it doesn't explain anything, just gives you the code for you to look at, and well, it's hard to understand.
I WANT TO MAKE THE PROGRAM BEFORE MORE YEARS PASS BY.
I have a teradata backend that uses auto increment. The form is databound i.e dragged a column to the form which gave me the navigation header etc.The problem I'm having is when user 1 opens a record the auto increment goes +1, let's say we're at 45 now, then user 2 opens a new record and it also goes to 45 as user 1 has not saved. Why is the databinding not locking 45 when the first user opens it
View 8 RepliesI've created an application, And now need to add the chat feature. It just needs to be basic, But im un sure on how to code one since i am still a beginner at Visual Basic. I know there is a way via TCP Listener using Net.Sockets, But im stuck there. I am totally out of my mind when i think ill know how to code. But here is how the chat will work[code]...
Server side, Is just to host it. I will host it on a windows vps with ports opened, and Anyone who downloads the program can connect to the chat. The username or Nickname of the user will come from 'My.Settings.username'. At this point I am willing to pay someone to code this project.
i just want some opinnion or suggestions regarding database softwares. we are going to develop a system for 20 or less users, i am planning to use MYSQL community server as our database to lessen the budget for that system, i just want to know if it is ok to use that version.is there a big differece between mysql community server, enterprise server and MS SQL Server in terms of handling data i.e security, speed, etc...
View 2 RepliesI am currently working on a project for school in which I am trying to implement a multi user login on one of my forms. I have an internal database connected in which one of my tables contains the user-names and passwords. I have a For/each loop to search the table for a matching username/password before allowing access to next form. The problem is even if the username/password is correct, my message box still appears to notify of invalid credentials, but still allows access to other form. The problem only occurs when I implement two For/each loops. With one, code works fine. Can any one see what might be wrong?
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how to make an application with a multiple user.
language: VB
resource: Visual Studio 2008 Pro(90-day trial)
Sql express (the packages when u download the VS 2008)
scenario: i will make database located in a server (LAN) and a multiple client that can access the server database to add,modify,delete records.Im not aware that building a multi-user application database is different from a normal one user application database. T_T.i read some guide and other walkthrough on building a database but it became confusing when it doesnt my requirements. coz when i try to open my database(.mdf) to connect from other client (in another station) it says its currently in use and connot connect to it. err. @_@..
give me some example code to insert rows of datagridview into a sql express database table? Also, how do I manage concurrency as it is a multi user application?
View 6 RepliesAlmost 2 months i try to find perfect solution for my project. I making one multi-user chat application with SERVER and CLIENT application. I read a lot of material about socket communication and try a million of examples all around, some in C# some in VB.net, but I can't find solution.Problem that every example and my try have is when 10-20 user chatting really fast, server reacting slow or whatever is, but final product is that two or many message show in one LINE. For example if i send string "test1" and an my friend, let's call him FRIEND1, send "test2" almost in same time, server sending it to all connected clients like this:stefanACM:test1FRIEND1:test2.I try to implement in my application "Asynchronous TcpListener & TcpClient" from jmcilhinney, but have same problem...
So, can anybody help me with this.I just need one server application that will recive connection, save IP and nick of connected user, and send every message that client sent to all connected users (of course without problem that I mention on beginning of post). On end, that when client disconnect just to close connection.From Client side I need just connect part, send and receive messages.
So in one line, I think I need BASIC EXAMPLE OF PERFECT MULTI USER CHAT CLIENT AND SERVER, without any hiden bug.If someone decide to help me with code,
I have made a windows forms application with a user login which queries a sql server database located on a central server. It currently has one sql server login which it connects to using a connection string in the app.config file. The user login is validated by querying a username table in sql server. I would like to make this a multi user application where after the user logs in, their credentials are stored and used by the the application to access the database with a sql server login. There will be 5-10 users.
View 3 RepliesI've got a problem with my latest project, I get concurrency error but I'm the only one working on the database.It's an sql server 2005 express database, and i'm making a remote connection. I have a related database or how do I say it, it's with relations. But the strange thing is that I can update the first table but the 2nd one not. Well here is my code, don't really know how to explain it better but I get an error when updating my orderinformation table but when only changing values in orders that table updates perfectly. [code]
View 3 RepliesI have been using access for my applications from over 4 years now. I realize its time to move on now and i need suggestions for a new database. Here are my requirements :should be able to connect it with Vb.net windows form frontend GUI - all database functions such as add/delete/edit/update will be done through the vb.net front-end only.Should be able to place the db on LAN and each client on the LAN can then access the centrally stored db through their individual front-ends.At the most 5-6 users will be reading/writing to the database at the same time , so the database should not crash or slow down Since i come from MS access background, i would like something thats similar to it so that i can learn and adapt to it quickly.Not very important, but i think its worth mentioning. This db will be the main central db for my .net application.My .net application will also be interacting with quickbooks and magento via some apis but ultimately all this data will go to the central db. So just curious, will there be any compataibility issues with the database that you suggest Should handle about 10 tables and around 10k records in each table Should be secure - just that i should be able to lock it up or anyhow prevent it being accessed from anywhere else other than the vb.net front-end.
Lastly, I would prefer it to be free to use if possible but not essential. I realize there are some topics like mysql vs sqllite and on databases, but pls understand i need suggestions for one that will be apt for the purposes i have listed above.
Edit : Just curious - Would i pushing the limits if i still stick to access - i understand access won't be good for multi-user access but i guess 5 users is not much ?
I am developing a VB.Net application. That application might be working on a LAN. MS Access as a backend will be used.
I have developed many single user applications, but don't know of multi user , LAN, manage DB etc. How do I make the program as Multi user on LAN. Data will be accessed at the same time. How to mange such things.
Our engineers use an application developed internally to perform risk assessments at a customers site. Sometimes on larger jobs a group of engineers will all carry out risk assessments together and will all need access to a single database file to all work on at the same time.
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Someone gave me a link to a Multi-User TCP Chat application once, but, there is a flaw in it, where it wont do special characters, such as Alt+1 will become a different character to the server than the one that was sent. Even I tried to see if the output was usable but it sees it as multiple chars, when it is only 1, and I can't find a link between what it sends and what the character is, so I can't just tell it based on whats sent what the char is, because I see no relation, I would have to type it out for each and every special character.
View 2 Replieshow to create a multi-user chatroom program. I don't have the server, but I have got a web hosting. I want to know how I can connect to the chatrooms by connect to my web hosting using with httprequest?And also, I would like to have code to allowed me to send the users private messages, ignore the users and kick/ban the users out of the chatroom.
View 10 Repliesdo this??& can I make a Main server like this?
View 1 RepliesI need to create a multi user VB.Net application that connects to Access 2007 and has 2 forms. How do I go about it?
View 4 RepliesI'm using SQL 2008 Express with a multi user VB.NET Windows application. Do I have to add each user to the SQL user account? Does NT AuthoritySYSTEM work? I do not know how this works. So far I have NT AuthoritySYSTEM in the Security-Logins of the Server. But do I have to add it also in the database? In the databse Security-User, I have the following:
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How do I make a Multi User CHat Program in Visual Basic Express Edition? I kind of want it like (Server) and then everybody whos a client connects to the server.
View 3 Replies