Concurrency - Restore A Dataset To The Previous State Before Updating The Database With A Data Adapter?
Dec 10, 2009
How do you restore a dataset to the previous state before updating the database with a data adapter? I have a concurrency update problem that I believe to be caused by this. The update fails during the update and a rollback command is issued using a SQLTransaction object. However, now the rowstates of the rows that did not have errors have been changed to unchanged. So this record is no longer availible to be inserted into the database. When I updated the value that could not be null and then test the second update which runs just as the first does then I get a concurrency error. The update code is below:
Only my local dataset updates when adding, deleting or editing records.The Source Database is supposed to update on issuing DataAdapter. Update(dataset )However, when I check my source database after running the operations it remains the same as the original.
i'm making a vb aplication (only my second one so dont be to cruel) and i'm just wondering how to make it so that when somebody closes my aplication down and open it back up it restores it to the same state, i've had a look on google and the only thing i can find are how to remember the size and position of the form using the registry and also using flat file databases to hold the values of all the text box's but is there an easier and more elegant way
when i try to insert data from database into dataset using data adapter, it takes long time, i want to use hourglass but i'm confused how or when i type the code so user will know that application still work.
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,
Honestly I do not understand why I need to write code to update a databse and why it stores it localy. I'd simply rather the system update the individual row after it is scrolled off of.
In either case since I guess I can't do that.
Here is some code in a button on a form
Try ItemsTableAdapter.Update(NewCreationsDataSet1.Items) LineCodeTableAdapter.Update(NewCreationsDataSet1.LineCode) Catch ex As Exception
[code]when I run my program and press this button Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles exceptionsButton.Click..I have my date range within a time that I know that my dataset should produce a result, but when I put a line break in my code here: adapter.Fill(ds)and look at it in debug, I show a table value of 0. If I run the same query that I have to produce these results in sql analyser, I see 1 result. Can someone see why my query on my form produces a different result than the sql analyser does? [code]I can also verify that the variables are passing the correct values. Can anyone please assist as to why this isnt working?
Code: Imports System.Data.SqlClient Public Class Main[code]....
and when I run my program, I have my date range within a time that I know that my dataset should produce a result, but when I put a line break in my code here:
Code: adapter.Fill(ds)
and look at it in debug, I show a table value of 0. If I run the same query that I have to produce these results in sql analyser, I see 1 result. Can someone see why my query on my form produces a different result than the sql analyser does? Also here is my schema for my two tables:
myCommand = New SqlCommand("SELECT VisitorID, VisitorName, Skill FROM tblVisitor LEFT JOIN tblSkill ON tblVisitor.SkillID = tblSkill.SkillID", myConnection) myAdapter = New SqlDataAdapter(myCommand)[code]....
then it catch an error as Incorrect Syntax near". which it points to myAdapter.Fill(myDataSet, "tblVisitor") not the Select command.
I'm developing an Ajax-based application which makes heavy use of server calls to a WCF layer that communicates with a DB.Whenever I effect from the client (an ASP.NET page) many calls within a short span of time to the underlying WCF services, the system hangs and goes into a idle state.
I have two Datagrids, One grid has all the customers garments on it with style number and contact length. The other grid has the users who have garment issued to them. the style number is in both grids. I need to loop through the users grid and say if the contract number is 1 from the first grid then the contract date on the second grid will be todays date + 365 days (year contract) I have looked at using a stored procedure and also a for each command but I am just getting stuck with it all. [Code]
I've made a dataset using the dataset designer, and I'm trying to add a column to reflect changes made to the database (added a column, nothing fancy). Is there a way to 'refresh' the dataset schema from the datasource without deleting my adapter (and all the methods and queries I've created)?
What I want to happen is that the button from my system will remove the previous data from database and then insert new data to database from text file. Im done with inserting new data. The thing is that I dont how to control or where to put the Delete Command from my code.
If i use the form.showdialog method to open a form, then input data.. when I close the form then re-open it the data is still there.Is there a way of restoring the forms original states, as it is on load?
I've created a "Loading" borderless Form that's displayed when loading records etc. I'm using the following to keep the loading dialog centered within it's parent.Works great except fo when the form is minimised estore- The loading form appears instantly while the parent (Owner) maximises with the usual VistaWindows 7 animated maximise.
What would be the best method to prevent the loading form appearing before the main form?
I have an Access Database in which I am trying to add a row through a dataset. I am able to add the record to the dataset but I can't write it to the live database.
Dim connectionString As String = _ "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:extraTEST.accdb;Persist Security Info=False;"
I'm new to vb.net and its database methods so I'm a bit confused by these datasets and grids and table adapters.
I'm getting:Concurrency violation: the UpdateCommand affected 0 of the expected 1 records.
On this line:frmMain.AccountsTableAdapter.Update(frmMain.DsAccounts)
I have a datagridview attached to a dataset. I also have a button that the user can press to update information in the datagrid based on a website. But I often get that error when it comes to actually updating the table.
I am checking to see if a textbox contains a number, or is null. If it is non numeric or null a message box appears asking the user to input the proper value. When the user clicks OK on the msgbox the program will continue to execute the code. I want it to stop executing the code and revert back to its default state as it would be if you just opened the program. What is the command for doing this so I can add to the if statement?
Dim numCheckV as boolean numCheckV = IsNumeric(Vinput) If numCheckV = False OrElse TextBox1.Text = "" Then MsgBox("Please enter voltage!") End If
On a form i have several text boxes binded to a bindingsource and including a datagridviewI have populated the textboxes with database fields successfully and the datagridview displays the correct information.I have the following code to save the information to the database but i cannot get it to work. [code] I have tried many code examples here in order to save the data, none of which has worked.Can anyone please help me with this?
I am having a problem updating an access database with new information from an updated dataset. the database consists of 4 columns: User_ID, Login_Name, Password, Access. The following code makes a connection to the database, fills a dataset with the data from the database, reads a txt file with user name and passwords, and should update the dataset and then the database. However, I keep getting an Syntax error on the INSERT INTO statement on the datest.Update(dsUser,"User") line. I have found multiple posts on here showing the correct syntax of how to update a database, but I can't seem to get it to work.
so I was originally having problems even saving the data, but I can now get it to stay in the dataset, and when I switch to another page it stays there when I go back to it. Although when I close the form and reopen it, the changed data has not saved. I know that it is because I have only updated the dataset and not the database, so was hoping someone could give me pointers of how to approach it.
I have a dataset (WW1Dataset) with one data table(WW1).(database used in an access database) I'm trying to filter the dataset e.g a user wants to filter by a chosen surname (SurnameTextBox.text) so the datset is filtered to display only those records wherethe surname column in the dataset matches SurnameTextBox.text.
I am writing a program that makes use of SQL databases using MSSQL Express 2008. I've just written code that updates data in the DB, but I noticed when I update an entry in one instance of the program, and then try to update the same entry in a second instance of the program it goes through. What I want is concurrency so if the entry is different from the original, updating is not allowed.
Here is the code I use to update entries VB that calls the class and checks for errors... Try If contactIsValid() Then Dim getresults As New groupfilladd If getresults.updatecontact(myParent.itemfound + 1, fnameTxBx.Text, lnameTxBx.Text, _ [Code] .....
On my form I have a datagridview which is bound to a 'Supplier' table in Access 2003. Once I click on a record on the DataGridView, textboxes below which are also bound to the same source are automatically populated with the relevant data. What I want is when I click update, that the records in the database are updated as well as the dataset but what happens is that the dataset is updated, I invoke the tableadapater.update method but no permanent changes are made to the database.
Below is the code attached to the 'Edit Supplier' command button.
Private Sub cmdEditSupplier_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdEditSupplier.Click Me.SupplierTableAdapter.Update(QuoteDataSet.Supplier)
I have got problem when using the SQLCommandBuilder class. For me it throws an error saying that the select statement does not return any primary columns.... Which is weird becouse i am sure it does since the select statement is "SELECT * FROM MyTable" I am prety sure that selects everything including the primary column which is set to primary , realy i checked and doublechecked.
Secondly i tried to manually set the column(0) as primary by setting it's property bu no such luck of making it work.
I have these two functions in a class that i instanciate an object from in the main program:
Code: Public Function GetDB(ByVal DBName As String) As Data.DataSetDim SQLAdapter As SqlClient.SqlDataAdapter = Nothing
Try_SQLdataSet = Nothing
[CODE]...
This Functtion fills the dataset and returns it to my main program where i do lovely stuff with it. (Just as a side note this is a SCADA system and i always need the entire DB which is never bigger then just a few ( 6 ) entries so i must go for "*" ^^). Good part is, this works like a charm, i love it. Now i need to reset a few status bits etc and i assume with the update command. And that is where my joy starts to get stomped on a bit.... The code:
Code: Public Function SetDB(ByVal dataTable As Data.DataSet, ByVal DBName As String) As BooleanDim SQLAdapter As SqlClient.SqlDataAdapter = Nothing Dim SQLCommandBuilder As SqlClient.SqlCommandBuilder
[CODE]...
Now this would have been a great and small sollution to updating datasets with the server but obviously it doesn't work. There is that pesky error about my table having no primary key and I know it's lying it just want to annoy me :P. But seriously I am puzzeld why that error wont go away and i have exhausted all the tutorials i can find on this.
