Manage Concurrency As It Is A Multi User Application?
Mar 2, 2009give 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?
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Multi-user Application - Updating All Clients When A User Updates Data (push Vs Pull)?
Aug 26, 2009I 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?
Make Multi User Application?
Mar 10, 2009I 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.
Create A Multi-User Application?
Sep 18, 2009I 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 RepliesCreate A Multi-user VB Net Application?
Feb 19, 2009I 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 RepliesMake A Multi-user Application?
Apr 11, 2009I 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 RepliesMulti-user Tcp Chat Application?
Jul 29, 2009I 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.
DB/Reporting :: Database For Multi-user Application
Jan 28, 2011i 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 RepliesMake Multi-user Application (database)?
Dec 7, 2009how 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. @_@..
Make Program Application Work As Multi-user?
Jul 25, 2007I 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.
Special Characters - Multi-User TCP Chat Application?
Jan 8, 2010Someone 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 RepliesCreate A Multi User Application That Connects To Access 2007
Feb 19, 2009I 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 RepliesDB/Reporting :: Using SQL 2008 Express With A Multi User .NET Windows Application?
Mar 26, 2009I'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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Method To Develop And Deploy A Multi-user Desktop Application?
Sep 17, 2009I have developed an application using vb.net. This application will run on approximately 15 machines at the main office and also roughly 10 machines spread over 3 different locations. I am using SQL Server Express edition in the backend. I deployed the application on the network using caspol but it is extremely slow. The Company Manager's perception is that because a script will invariably have to be deployed on each client machine to configure CASPOL, that the solution is not viable.
What is the best method to develop and deploy a multi-user desktop application?
Multi-user TCP Chat Application Doesnt Append Text
Apr 6, 2011I've been trying that example application at [url]...
I'm just using the client part to connect to an exiting server application. It works OK up to the point where it appends text into the[code]...
DB/Reporting :: Multi User - Windows Application With Back End As SQL Server 2008 Express
Mar 17, 2009I'm working on a multi user VB.Net windows application with back end as SQL Server 2008 Express. The SQL Server is installed on the intranet network drive. This is the connection string I will be using. Is this correct?
Data Source=.SQLEXPRESS;AttachDbFilename=Q:DatabasePrintDB.mdf;Integrate d Security=True;Connect Timeout=30;User Instance=True
ADO.NET Concurrency Single User
Jan 16, 2009I'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 RepliesEvent Consumption For Concurrency In A Multicore Application?
Jan 18, 2010Target machine 4 core AMD I have an event that is raised my the main thread of the application. The event is consumed by several different classes in the application. I want them all to run concurrently up to the max cores available and then que the rest in order.The work routine in each class is relatively small but concurrency is the goal.Considering this.
A. Create a background worker on each classes initialization and have the event handler start the worker.
B. Create a delegate to the do-work sub that is called by the event handler
A- Pros - worker is only created once and reusable so only pay creation cost once.
A-Cons could create a ton of workers that consume resources eventually.
B- Pros Smaller thread pool
B- Cons Lot of overhead
Include Logic In Application To Handle Concurrency Violation?
Nov 5, 2008the problem here happends every time i tried to change a record that's been allready saved.Private Sub PropuestasBindingNavigatorSaveItem_Click_1(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles PropuestasBindingNavigatorSaveItem.Click
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Get Informations From A Database To Manage The User Access Level?
Sep 3, 2008I'm writing a form that get some informations from a database to manage the User Access Level.The way i do that is to Fill a Dataset by using a DataAdapter and the Bind some controls to the Dataset.The controls i binding are a ListBox, a Textbox, and five Checkboxes.All are fine with this controls. I can delete values and update values, i can choose a record from my ListBox and the values of this record to be desplayed on the othrer binded controls and so on.
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The Update() Of An Application Doesn't Perform Any Updates Or Deals With Concurrency?
Nov 10, 2009I have written an application to perform a simple CRUD operation i've used MVC design pattern... DAL was designed using the wizard. I was able preserve the olds value of teh fields of EMployee class using a seperatemethod
PreserveOldValues(){ //code}
in the SearchByIndex() i call the fill method and i used the data to initialize the current Employee object also i preserve those values using PreserveOldValues() the i call update() and internall i pass the preserved values......However it doesnt do concurrencies and updates..
Manage Queries In Application?
Jan 6, 2012I have an application that works together with a SQL database. This database has more than 40 tables and my applican has to extract different situations from those tables.
I have predefined some queries for the situations that I know they need to be in the application.
The idea is that I need kind of a module in which an user can create his own situation based on the tables, views, functions and procedures that already exist in the database. Something like it is in SQL. There has to be a library or something which will read my sql database directly from my application and which allow the user to create his own queries and situations.
.net - Memory Usage In WPF Application - How To Track And Manage
Feb 12, 2012I have a small-scale WPF application using VB.net as the code behind and I want to add certain features, but i'm concerned about performance.
1) My app interacts with a third party database to display "realtime" data to the user. My proposed method is to create a background worker to query a database every 30 seconds and display the data. I query about 2,000 records all long integer type, store them in a dataset, and then use LINQ to create subsets of observable collections which the WPF controls are bound to.
Is this too intensive? how much memory am i using for 2,000 records of long int? Is the background worker querying every 30 seconds too taxing? will it crash eventually? Will it interfere with the users other daily work (excel, email, etc)?
2) If an application is constantly reading/writing from text files can that somehow be a detriment to the user if they are doing day to day work? I want the app to read/write text files, but I don't want it to somehow interfere with something else the person is doing since this app will be more of a "run in the background check it when I need to" app.
3) Is there a way to quantify how taxing a certain block of code, variable storage, or data storage will be to the end user? What is acceptable?
4) I have several list(of t) that I use as "global" lists where I can hit them from any window in my application to display data. Is there a way to quantify how much memory these lists take up? The lists range from lists of integers to lists of variables with dozens of properties. Can I somehow quantify how taxing this is on the app or the end user?
Client Server Application - How To Create, Manage And Strategy
Dec 6, 2009Im a new in this VS2008. But i have some foundation of programming in VB6.0. So im planning to create this application using VB since im familiar in that language.I downloaded a Visual Studio 2008 and SP1 - now on its 90-day trial, and planning to buy the full version depending if it will meet my needs. I just read afterwards the conditions and how to buy it. I hope its free shipping and credit card is acceptable.^^
I need to make an application something like a reporting system, my plan application is a client-server application. Currently im reading the How to topics and some walkthroughs so far so good. Now here are some sort of details and target need to fulfill.
1. An interface from client that will input the data from the multiple-user , including images and these data will be saved in database/table remote server (center database server) LAN.
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Single User To Multi User?
Oct 19, 2009Suppose 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 RepliesManage A Large Number Of Similar Controls In A User Interface (such As Button Or TextBox Controls)
Aug 23, 2011There is newer code in a follow up post. I suggest using the code in the later post rather than the code in this one. You can still read this post though. When designing a user interface, one should be conscious of how many individual controls are required to implement the functionality. In some cases an initial design may begin with many buttons or textboxes (for example) but then further review of
the actual required functionality allows for a reduction in the number of unique controls.
But other times, there isn't a better way (which will still make sense to the user of the application) then to have a series of many repeated controls. So in the cases where one can be certain that the best UI implementation for an application will require the use of multiple copies of a given control, then it often becomes necessary to maintain some method of managing all of those controls at various points
throughout the application. Doing so typically requires that one build up some collection of controls which can then be accessed by index in order to work with any given control; but this can lead to a lot of clutter in the code file which handles these control's events. For instance there will be some kind of collection declaration, some recursive routine to find all of the controls of interest, and then any number of event handler methods with long lists of Handles clauses, or additional code loops to wire up the event handling for each control.
Purpose Since most of this functionality could be considered a requirement regardless of the type of control being managed, or its required functionality, it may make sense to wrap all of the control management functionality into a single class. And since our first requirement is a collection of controls, then a base collection class could be the perfect starting point for our control manager. There are a number of existing thread around this topic, with some recent (at the time of this writing) ones being:[URL]..In this, and related, threads I have posted examples of a simple TextBoxManager and ButtonManager control. But again, with so much similar functionality required regardless of the control being managed, it would be technically possible to create a generic ControlManager(Of T As Control) class which can manage any type of control.
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So in summary, one can facilitate managing a large number of user interface controls by building a "control manager" class which both encapsulates the list of control instances, and deals with adding and removing defined event handlers for every control it manages. The generic control manager class itself can be inherited and extended into a more specific class on a per-application basis in order to provide more application-specific functionality. Reed Kimble - "When you do things right, people won't be sure you've done anything at all"
C# - How To Do Multi User Editing
Jul 21, 2011I 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.
Create A Multi-user Chatroom?
Jun 26, 2011I 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 RepliesDataAdapter Useful For Multi-user Applications?
Jan 24, 2011i 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
Make A Multi User Database?
May 11, 2011How 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.