I'm encountering a hang when the program tries to access the fruit database. I've already enabled network access MSDTC on both my development computer and the SQL Server server.
I have a simple Windows Service that reads from an Excel spreadsheet and imports the records into a SQL Server 2000 database table. Before it loads it checks if the file has been successfully imported before (using filename) and whether any of the records in the file have been imported before (using primary key). If these checks are ok I load the records into a datatable and then update the datatable to the database.
However, I need to do this in a transaction as I want to ignore the whole file if there is an error. The file goes to a discarded folder and the user gets an email with why the import failed. (This is likely to be because the store the record is for is not yet added to the database and the referential intergrity of the db fails). If there is no transaction the records before the failure record are imported. When the file is imported again (the store has been added to store table) the file is then rejected because duplicate records are already in the db.
I'm currently working on a legacy project in VB.NET 2.0.The project has a very funny DAL-layer which does not incorporate transactions :-|Anyway, it's my job to make some parts of the program transactional and I don'thave access to the DAL layer code.So I'm trying to put entire sections of code inside single TransactionScope.
Running this against both our production and test Oracle 11g database sporadically (or if there is a pattern, I haven't found it yet) generates the Oracle Error:ORA-02049: timeout: distributed transaction waiting for lock Since this is the only process running against the test database, there shouldn't be any issue with different users competing for a lock.
I came accross TransactionScope as I try to resolve an issue bothering on the use of Transactions on Typed DataSets. But when I tried to implement it, my intellisence does not recognise it. I have to Import System. Transaction. TransactionScope but it is not recognised. How do I use it cos it seems like it holds some clues to my problem?Only performance counts!
I have some VB.NET code that creates a TransactionScope instance:
LoggingUtility.LogDebug("UpdateCallTable", "SatComCallDataImporter", "About to associate call data with contracts") Using ts = New TransactionScope() LoggingUtility.LogDebug("UpdateCallTable", "SatComCallDataImporter", "Getting all unimported SatCom calls")
My application is throwing an exception on the call to the creation of a new TransactionScope, with "Object reference not set to an instance of an object.". The exception isn't thrown on my development machine or my test machine; only on the customers production machine, and I have no idea why. I've placed debug lines immediately before and after this line so I'm positive it is this line causing the problem.
A have used TransactionScopes throughout the application and this is the only place throwing the exception on the client machine."About to associate call data with contracts" gets written to the log and the next log entry is the "Object reference not set to an instance of an object".
Code works fine if I move it out of a transaction.I've been struggling with this for 4 days now and have got no closer.
I use Microsoft ODBC For Oracle, and process a distributed transaction with ransactionScope, but, the code throws a error: ERROR [HYC00][ORACLE][ODBC]option not implement, my code is in vb.net.ere is my code:
sub Main() dim strConn1 as string = "Driver={Microsoft ODBC for Oracle};Server=server1;UID=user1;PWD=pwd1;"
I have trouble using the transactionscope on SQLite, i am using the following code. Changes are still commited to the database while i don't call the ts.Complete() function.
Using ts As New System.Transactions.TransactionScope() Using sharedConnectionScope As New SubSonic.SharedDbConnectionScope() ' Do your individual saves here'
I'm trying to incorporate TransactionScope into my code and am failing at the first hurdle. I am unable to open a connection inside TransactionScope block. I get exception Connection Not Open.
Public Sub PerformDBWork() Dim cnA As New OleDbConnection(My.Settings.DB_CONN_BUSINESS) Try cnA.Open()
[code].....
My cnA.Open() fires as expected but my call to cnBusinessDB.Open() fails.
Im trying to make a web service in VB.net is their a way that i can return the results that i get from LINQ. ie "return objreturnLINQResults" I have tryed to set my Public Function GetAlarmsByGUIS(ByVal DeptGUID As String, ByVal IdNumber As String) As Linq.DataContext . i just keep getting errors.
Public Function GetAlarmsByGUIS(ByVal DeptGUID As String, ByVal IdNumber As String) As Linq.DataContext Dim lqAlarms As New linqAlarmDumpDataContext
I am using LINQ with Entity Framework, and I need to get the SQL server timeCan anyone tell me how can I create a method so it retrieves the current server time?
I was looking at using linq to sql (or EF) rather than in linedynamic sql within my application but have hit a possible issue. My application modifies data against any number of random databases accross several sql instances, linq appears to structured towards a single database scenario. Would it be best to just continue using in line sql or is there a method of using linq without tying it down to a single database? An example of what I'm doing at the moment:
I'm having trouble with a LINQ to SQL query getting the min value using Visual Basic. Here's the SQL:
SELECT RC.AssetID, MIN(RC.RecCode) AS RecCode, JA.EngineerNote from JobAssetRecCode RC JOIN JobAssets JA ON JA.AssetID = RC.AssetID AND JA.JobID = RC.JobID WHERE RC.InspState = 2 AND RC.RecCode > 0
I'm working on an ASP.NET 4.0 site, which I inherited ownership of. It has a number of existing LINQ datasources pointing to individual tables. For example, to the Patient Encounter Summary table in SQL Server. The problem is in displaying the data there. It's a normalized database, so that table contains (for example) the provider ID, rather than the provider name.
It's simple enough to join the Patient Counter Summary to the Providers table (in SQL)... but how does one do that in ASP.NET? I'm not sure of the correct nomenclature, but the 'mid layer' is VB.
I'm using Linq to Sql and have a stored proc that won't generate a class. The stored proc draws data from multiple tables into a flat file resultset. The amount of data returned must be as small as possible, the number of round trips to the Sql Server need to be limited, and the amount of server-side processing must be limited as this is for an ASP.NET MVC project. So, I'm trying to write a Linq to Sql Query however am struggling to both replicate and limit the data returned. Here's the stored proc that I'm trying to convert:
I know how to select items from an array with LINQ, but what I can't figure out how to do is access a database using an IQueryable. I connected the database to my project, added two classes from the database to the "LINQ to SQL" .dbml file and saved it. In my programming assignment, I am not supposed to create a data source (table thing) to display the data, but update my own interface manually. In order to do it, I was told to instantiate this:
Private dogs As System.Linq.IQueryable(Of Dog)
(Dog is a class that I added to my .dbml file from the database file)Also, I am told it involves using a method
I have a programmer who is using VB and LINQ; and I have a MySQL database that is running on a linux server. My programmer tells me that:he cannot connect to the MySQL database via LINQ if he was able to connect then it would require all sorts of rewriting I don't know anything about LINQ but I thought it was an ORM. As such, any DB server that is supported should work just fine? Right? OK, so maybe it's not an ORM... maybe it should generically connect to ODBC and render similar results?
I have a stored procedure (I cannot edit) that I am calling via linq.
The stored procedure returns values (more complex but important data below):
Customer Stock Item Date Price Priority Qty -------------------------------------------------------- CUST1 TAP 01-04-2012 £30 30 1 - 30 CUST1 TAP 05-04-2012 £33 30 1 - 30 CUST1 TAP 01-04-2012 £29 20 31 - 99 CUST1 TAP 01-04-2012 £28 10 1 - 30
I am trying to limit this list to rows which have unique Dates and unique quantities in LINQ. I want to remove items with the HIGHER priority leaving rows with unique dates and qty's.
I have tried several group by's using Max and order by's but have not been able to get a result.
Is there any way to do this via linq?
EDIT:
Managed to convert brad-rem's answer into VB.net.
Syntax below if anyone needs it:
returnlist = (From p In returnlist Order By p.Qty Ascending, p.Priority Group By AllGrp = p.Date, p.Qty Into g = Group Select g.First).ToList
I have been using DBTransaction for my current projects that access a single database. However, I read some documentation on TransactionScope and was wondering in which scenario would using TransactionScope be better? Or should I be replacing DbTransaction calls with calls to TransactionScope?
I have limited experience in VB.net and have become stuck. I have tried to search for answers on other threads without success.I have an application that displays real time data.Queries are made to a MySQL database on another PC over the internet every 10 seconds to gather the most recent data.I have done the query within a BackgroundWorker so that the GUI is still responsive while the query is answered.What I've done works great for several hours or maybe for a couple of days but then the DoWork task appears to hang.
The code I'm using is to run the background worker is:
vb If Not(backgroundWorker1.IsBusy) Then Me.backgroundWorker1.RunWorkerAsync() End If
The backgroundWorker runs just once and there's very little code in the DoWork routine:
vb Private Sub backgroundWorker1_DoWork(ByVal sender As Object, ByVal e As System.ComponentModel.DoWorkEventArgs) Handles backgroundWorker1.DoWork rs = New
[code].....
Is there anyway I can set up a timeout on the maximum allowed time that the DoWork task can be active for? And if so how would I then go on to stop the backgroundWorker?I understand that CancelAsync isn't going to help as my DoWork task is not repeating as it runs once only, then stops and 10 secs later I run it again.
When i try to build a project, vb hangs and displays this message in the notification area Microsoft Visual Basic Express 2010 is Busy. i have to end up using Task Manager to end the process i have been using VB Express for about a year and have never had this problem. i have tried to re-install VB 2010 express, no joy.
ApplicationName has stopped workingA problem caused the program to stop working correctly.Windows will close the program and notify you if a solution is available.
Here is my code: Private Sub OpenFile() Dim OpenFileDialog As New OpenFileDialog
Its been running in production for over a year and this is the first time I saw this behaviour. The application is a VB.NET Console Application which is triggered by MQ server. This application uses a class library which is part of the same project(Say 'abc.dll'). In production around 40+ instances of this exe are running and all of them use the some of the functions from 'abc.dll'.
Last week, we noticed that all the 40 instances were shown to be running in the task manager but they were not doing any activity. There was no exception thrown or error logged in Application logs or System logs. To frantically debug the problem, I tried isolating the problem.
With all these 40+ exes hung up, I wrote a small aplication which would use a reference to this 'a.dll', create an object of one of the classes in that dll and execute a method in there. I was printing console.writelines in between to see to which point it gets to before erroring out.
To my surprise, I found that at the point where I was creating an object of a class in 'a.dll' this sample test application would also hang just like the others. No exceptions thrown. So I killed all those applications as a last resort and then when I restarted all of them, everything worked fine.
I couldn't find any explanation for this behaviour. Since it was a critical error affecting a production system(blanking out the application for 3+ hours), I have to give a very good explanation as to why this would occur. how it can be prevented in future.
(Side note: the servers running these appilcation do not have a maintenance schedule and are supposed to be up for couple of months together.
When using the Dataset Designer in VS 2010 I add a new query.It adds with no issue.Add another,starts to hang. Add another and now it can hang for hours.I use task manager to kill VS 2010 after 30 minutes.Go back into the same table adapter query, modify it, save it.Works in seconds.Add another query, hangs, hangs, hangs.I have seen posts about this going back to VS 2008.I have No Add-Ons loaded, what is causing this issue??
I have this code to upload to a ftp server. It works but the problem is it freezes the program and sometimes you can end up waiting for long time and not even know its working. Code: Dim clsRequest As System.Net.FtpWebRequest = _ DirectCast(System.Net.WebRequest.Create("ftp://" + txt_ftp_username.Text + ":" + txt_ftp_password.Text + "@" + txt_ftp_server.Text + ":" + txt_ftp_port.Value.ToString + "/" + txt_ftp_dir.Text + "/" + txt_ftp_name.Text), System.Net.FtpWebRequest) [Code] ..... Can this code be modified so that it will run without freezing the program and then just add a button labelled "STOP" to stop the ftp connection/upload?
I have downloaded SP1 and installed it,I have an applciation with 10 form and numerous classes and dialogs. When I right click a form in the soultion Explorer window and choose view Designer VS hangs for anything upto 10 mins. Is there anything that I can disable/ enable to stop this hapening. The only Language that I will be developing in is vb.net.
Im developing several applications under Visual Studio, and now have a real nightmare in hands. When i start to debug, VS hangs completely. Windows allows me to start task admin, and close the "devenv" process.I have serious problems here. I need to deliver my projects before the deadline!
Win 7 Pro 32 bits, VS 2010 SP1, running on HP computer based on Intel i5, 4gb ram. everything works as intended, except VS. When debug crashes, the devenv process uses about 25% of CPU and 250~400Mb of ram.