the 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
[Code]...
My users are getting this error when trying to update the database:
"Concurrency violation: UpdateCommand affected 0 of the expected 1 records"
All the users are doing is clicking a button which updates a record.No two users are updating the same record or even within the same column. They could be updating within the same row but still not the same record.It seems to be happening when the program is open for a little while and they come back and try to update the database through the program. I have read a little bit about this error but none seem to lead to a clear solution.It seems like the database connection is timing out due to inactivity?Here is my update command:
vb.net
Private Sub btnComplete_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnComplete.Click
Me.txtComplete.Text = Date.Today[code].....
I'm having an issue with a concurrency violation when I save my data(only on one form). All other data forms are working fine. This form has a lot of code, so to isolate the problem I added a new form to the project and dragged the table from my datasource, in detail, to the form. this is the only code in the form,
[Code]....
I am trying to make a simple demo of a DataGridView bound to a database table. I want to add a row, delete a row, and save the table. I used the IDE to do just about everything. It created the BindingSource when I set the datasource of the DataGridView to a table of a DataSource I added to the project.
Now the only code looks like this:
Public Class Form1
Private Sub DataGridView1_CellContentClick(ByVal sender As System.Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles DataGridView1.CellContentClick
End Sub
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
[Code] .....
I set the AutoIncrementStep to 1 in my Key field in the dataset (the .xsd). I left the Key field visible in the DataGridView and it seems to be adding the correct Key when a row is added. However, I still occasionally get the "concurrency violation" error if I just mess around with these 3 buttons. Any idea why/how to prevent that?
get around the following problem please?I have an Access database which can be accessed by more than one instance of my application (which is) a Form with a DataGridView on it.I populate the DGV with
Form1.Validate()Form1.CHECKLISTBindingSource.EndEdit()Form1.CHECKLISTTableAdapter.Update(Form1.chkDataSet.CHECKLIST) The Access Database can then be updated via the DGV by a button click (which runs the code above (to copy across the latest copy of the DB) and then runs the code below to copy your changes to the DB)
Form1.CHECKLISTTableAdapter.Fill(Form1.chkDataSet.CHECKLIST)
Form1.DataGridView4.DataSource = Form1.CHECKLISTBindingSource
Form1.DataGridView4.Refresh()
The Access table is basicaly a 'Time' Column and a 'Name' Column.
[Code]...
I'm trying to update a Access database. I'm new to this and I've reviewed an Ado tutorial early today. I'm trying to apply what is taught but I'm getting an error message and I can't seem to get passed it.
In my code I have an Add, Update, and Delete process. The Add and Delete processes work just fine. It is only when I go to update the database that I get the following message."Concurrency violation: the UpdateCommand affected 0 of the expected 1 records."
[Code]...
When my project starts, it first checks for the existence of certain rows in the database. During testing, I often delete these rows, as they get kind of messed up over time due to all the odd tests I am running. For that reason, if when the project starts, if the records are not there, the program first creates them.The records are pretty static over the lifetime of the project, so they are held in a dataset for ready access from various parts of the program. Therefore, if the records are not in the database, the records are added to the dataset, and the dataset is updated back to the database. This works without any issues.However, one of the easiest actions to take will cause one of these records to change two fields, and a new record will be added. Those are all the changes that are caused by this action. Those changes are then updated to the database...or so I hoped, but when I try that I get an exception stating:[code]I have looked at the datatable that is being updated, and there are, as I expect, two records being changed. One of the records is the new one that is being added, while the second record is the record that was changed. I have noted that the change is, in fact, different from what is in the database, so this really IS an update.
However, I also noted that if I then stop the program and start it again, all is well. This indicated to me that it was actually the routine that created the records that was causing the trouble. Therefore, to test this out, I tried a totally horrible solution. I altered the method that writes to the new records to the database so that after it wrote each record, it would clear the whole dataset and fill it all again. That's obviously a terrible thing to do, but it works. If I write each record, throw out the dataset and re-create it, then I don't get any exceptions when I later try to modify it.This makes no sense to me. What am I doing in that first method that could be putting the Dataset into a state where it fails on any further modifications? I should add that the code that actually pushes the changes to the dataset down to the DB is the same for both methods. In fact, the database is updated in an UpdateDB method that is called from that first method (which creates the initial records if they are missing), as well as being called by the other methods that alter the dataset. I have also confirmed that ANY alterations I want, whether they add, remove, or just alter records, works fine. It is only that one method that creates the initial records that is causing me trouble. Moreover, it is not the actual update of the DB that is doing it, since that same method works fine ever after. Further testing has showed that the issue is row by row. As each initial row is added, it can't be modified by any other code until the dataset has been re-read from the DB. url...
A concurrency violation error? It happens on this statement:
CODE:
It thinks I'm using a key value of 1 when the actual value is really 1218. I'm using a command builder. The attachments show the value of the key value and the value of the update text values. By the way, I can insert data but not update it.
I'm having some trouble updating changes I made to a datatable via a dataadapter. I am getting "Concurrency violation: the UpdateCommand affected 0 of 10 rows"
'Get data
Dim Docs_DistributedTable As New DataTable("Docs_Distributed")
Dim sql = "SELECT DISTINCT CompanyID, SortKey, OutputFileID, SequenceNo, DeliveredDate,
[code].....
This code used to work but for some reason it doesn't anymore. I get the error "Concurrency violation: the DeleteCommand affected 0 of the expected 1 records." I checked to see if the values were in the db and they were, by the way I'm using Access 03. I commented out the try/catch block and got the error when trying to update the ds.
[Code]...
im using a sqldataadapter, dataset and bindingsource to connect to a table. i retrieve all records from the database and i change the data on a field then update changes to database. when i try to change back to original value i get a Concurrency violation error (concurrency violation: The updatecommand affected 0 of the expected 1). this is the
Try
Me.Validate()
Me.sqlBindingSource.EndEdit()
Dim slqCmdBuilder As New SqlCommandBuilder(sqlAdapter)
[Code].....
When I run the following code I get the error "Concurrency violation: the DeleteCommand affected 0 of the expected 1 records.", I know that this happens when the data is changed in between pulling it from the database and sending it back but, the database is not being edited.
View 6 RepliesNone of the "answers" that I have been able to find, address the problem. I am using oledb to read and update a MS Access DB in an ASP.NET application.I read the member dataset and fill it using the data adapter.I modify the row of data in the dataset.I then use the data adapter to update the row and get the error shown in the subject.
I am an experienced developer using ado.net on sql server windows application via the data adapter, so am familiar with how this should work.
I have searched everywhere and am hoping that someone here at Microsoft might have the answer.
I keep getting the above error when trying to update a record from a SQL Server DB TableWhat exactly does this Error Message mean?
View 3 RepliesI have a single user app that I wrote and have been using for more than a year that uses an Access 2003 database. Today, out of the blue, I started getting a DB concurrency violation whenever I tried to update one particular table in the database. After trying to troubleshoot what the problem might be, I just deleted that table and recreated it and the problem went away.
View 2 Repliesi have this delete code
My search
Public Sub mnamesearchdata()
'search data
Dim blnfound As Boolean
blnfound = False
[code]....
My Database In case. Having weird issues also were my database will be wiped out. Having 0 record.
[URL]
My client recently got this error but I can't reproduce it on my pc. Any Idea what the problem could be. I have a master/detail scenario. So I have a grandparent/parent relationship, so when I select a product from my product combobox it displays the relevant results from the Result_Header table in my first datagridview.
Then I have a parent/child relationship so that when I select a result_header item from my first datagridview it displays the child records from the Result_detail table. If i'm adding a new Result_Header and then click save, I search for existing tests for the chosen product and insert them as new datarows into the Result_detail table. then I can update the child rows and click the second save button and it saves what I edit. Quite complicated.
Dim data As DataSet
Private dbpath As String = My.Settings.dbpath
Private con As New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;" _
& "Data Source=" & dbpath & ";Persist Security Info=False;")
[code]....
I am working on a program whereby insert, update and delete of database is required, i have been able to do so successfully but the above error occurs when i tried to insert a new row of data into the database and tried to edit it and update it to the database. The database platform i used is SQL server 2005 and i am using datagridview to display my data, my primary key is "s/n" which is an auto number, however, whenever after i insert data into the database, the newly added row has the "s/n" column blank shown in the datagridview and after i edited that row and tried to update it, the error occurs.
Imports System.Data
Imports System.Data.SqlClient
Imports System.Threading
Imports System.Text.RegularExpressions
[code]....
In CRUD application development we have to face the issues with concurencies in Ids such as Generate and display UNique EmployeeIDs on forms. Currently i'm writting .DLL file that has a class that will handle concurrencies.
But i'm puzziled with the Question, is this concurrency handle is part of the software developer or Database developer?
Target 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
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 RepliesI 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..
We are using VB.NET and ASPx for our project. we would like to separate the aspx pages and put them on the IIS server (web server) on one m/c and the business logic and DAL layer on another IIS server (application server) on a different m/c .The database is on another m/c. Is such a configuration possible ? If so how can it be implemented?
View 2 RepliesI have a table, lets call it Objects. It has a predefined set of records looking like this:
ObjectId ObjectName
1 Salmon
2 Trout
3 Seabass
4 Shark
Etc..
So, this I would like to implement somehow as an enum. But what's the best way, implement it in the database creating tables for it or in the application logic in an CommonEnums codebehind file etc?
I need to include a calendar in my application
the best thing would be to include an outlook like calendar with its functionality
i have no idea how where to begin.
The application uses ADO.NET to invoke sprocs for nearly every database operation. Some of these sprocs also contain a fair amount of domain logic. The data access logic for each domain entity resides in the domain class itself. ie, there is no decoupling between domain logic and data access logic. I'm looking to accomplish the following:
[Code]...
I wanted to include an Enum of fractions in an application.
Enum fractions
1/8
1/4
3/8
1/2
End Enum
This produces a 'Statement cannot appear within an Enum body" Error.
Is there a way to make this Enum work?
I hv developed a vb2005 based win form application. I would like to include application registration module.The planned i/p fields are usr name, productID. Based on this two filelds a unique registration key will be produced.
View 4 RepliesHow can i include an external file in a XBAP application? For example a .dat file where i need to extract some data from? I want everything to happen inside the .xbap file, is that possible?
View 1 RepliesI was able to create an application in VB.net that talks to a SQL Server CE database.Now i want to deploy this application using the publish feature with clickonce.An issue im having tho is when I install the application on another computer it keeps looking for my sql server on my development pc.
Ive added the .sdf when i package my solution but its still an issue.How do I change my connection string to connect to the .sdf file that I included in the package? this is my current connection string which looks at the sql server: connectionString = " Data Source=CHRIS-PCSQLEXPRESS;Initial Catalog=ce_db;Integrated Security=True"