I'm trying to connect to an Azure db using pyodbc and keep getting this error.
My connection string:
"Driver=ODBC Driver 17 for SQL Server;Server=company.database.windows.net;Authentication=ActiveDirectoryPassword;Database=My_Database;UID=DOMAIN\UserName;PWD=********;"
Each time I connect it returns error The server has not found anything matching the requested URI
The strange thing is that when I try to connect with these credentials from inside SSMS, the error I get is Windows logins are not supported in this version of SQL Server.
All the other questions with this error are on web apps and html pages, so I'm very stuck.
I figured it out.
The problem was that I was using UID=DOMAIN\UserName;. When I switched it to UID=username#domain.com; the connection worked.
Hope this helps someone else with the same problem - there are not many resources on this error.
I am experiencing database connection errors with an ASP.NET application written in VB, running on three IIS servers. The underlying database is MS Access, which is on a shared network device. It uses Entity Framework, code first implementation and JetEntityFrameworkProvider.
The application is running stable. But, approximately 1 out of 1000 attempts to open the database connection fails with either one of the following two errors:
06:33:50 DbContext "Failed to open connection at 2/12/2020 6:33:50 AM +00:00 with error:
Cannot open database ''. It may not be a database that your application recognizes, or the file may be corrupt.
Or
14:04:39 DbContext "Failed to open connection at 2/13/2020 2:04:39 PM +00:00 with error:
Could not use ''; file already in use.
One second later, with refreshing (F5), the error is gone and it works again.
Details about the environment and used code.
Connection String
<add name="DbContext" connectionString="Provider=Microsoft.Jet.OLEDB.4.0;Data Source=x:\thedatabase.mdb;Jet OLEDB:Database Password=xx;OLE DB Services=-4;" providerName="JetEntityFrameworkProvider" />
DbContext management
The application uses public property to access DbContext. DbContext is kept in the HttpContext.Current.Items collection for the lifetime of the request, and is disposed at it’s end.
Public Shared ReadOnly Property Instance() As DbContext
Get
SyncLock obj
If Not HttpContext.Current.Items.Contains("DbContext") Then
HttpContext.Current.Items.Item("DbContext") = New DbContext()
End If
Return HttpContext.Current.Items.Item("DbContext")
End SyncLock
End Get
End Property
BasePage inits and disposes the DbContext.
Protected Overrides Sub OnInit(e As EventArgs)
MyBase.OnInit(e)
DbContext = Data.DbContext.Instance
...
End Sub
Protected Overrides Sub OnUnload(e As EventArgs)
MyBase.OnUnload(e)
If DbContext IsNot Nothing Then DbContext.Dispose()
End Sub
What I have tried
Many of the questions on SO which address above error messages, deal with generally not being able to establish a connection to the database – they can’t connect at all. That’s different with this case. Connection works 99,99% of the time.
Besides that, I have checked:
Permissions: Full access is granted for share where .mdb (database) and .ldb (locking file) resides.
Network connection: there are no connection issues to the shared device; it’s a Gigabit LAN connection
Maximum number of 255 concurrent connections is not reached
Maximum size of database not exceeded (db has only 5 MB)
Changed the compile option from “Any CPU” to “x86” as suggested in this MS Dev-Net post
Quote: I was getting the same "Cannot open database ''" error, but completely randomly (it seemed). The MDB file was less than 1Mb, so no issue with a 2Gb limit as mentioned a lot with this error.
It worked 100% on 32 bit versions of windows, but I discovered that the issues were on 64 bit installations.
The app was being compiled as "Any CPU".
I changed the compile option from "Any CPU" to "x86" and the problem has disappeared.
Nothing helped so far.
To gather more information, I attached an Nlog logger to the DbContext which writes all database actions and queries to a log file.
Shared Log As Logger = LogManager.GetLogger("DbContext")
Me.Database.Log = Sub(s) Log.Debug(s)
Investigating the logs I figured out that when one of the above errors occured on one server, another one of the servers (3 in total) has closed the db connection at exactly the same time.
Here two examples which correspond to the above errors:
06:33:50 DbContext "Closed connection at 2/12/2020 6:33:50 AM +00:00
14:04:39 DbContext "Closed connection at 2/13/2020 2:04:39 PM +00:00
Assumption
When all connections of a DbContext have been closed, the according record is removed from the .ldb lock file. When a connection to the db is being opened, a record will be added to the lock file. When these two events occur at the exact same time, from two different servers, there is a write conflict to the .ldb lock file, which results in on of the errors from above.
Question
Can anyone confirm or prove this wrong? Has anyone experienced this behaviour? Maybe I am missing something else. I’d appreciate your input and experience on this.
If my assumption is true, a solution could be to use a helper class for accessing db, which catches and handles this error, waiting for a minimal time period and trying again.
But this feels kind of wrong. So I am also open to suggestions for a “proper” solution.
EDIT: The "proper" solution would be using a DBMS Server (as stated in the comments below). I'm aware of this. For now, I have to deal with this design mistake without being responsible for it. Also, I can't change it in the short run.
I write this as an aswer because of space but this is not really an answer.
It's for sure an OleDb provider issue.
I think that is a sharing issue.
You could do some tries:
use a newer OleDb provider instead of Microsoft.Jet.OLEDB.4.0. (if you have try 64 bits you could already have try another provider because Jet.OLEDB.4.0 is 32 bits only)
Implement a retry mechanism on the new DbContext()
Reading your tests this is probaly not your case. I THINK that Dispose does not always work properly on Jet.OLEDB.4.0 connections. I noted it on tests and I solved it using a different testing engine. Before giving up I used this piece of code
GC.Collect(GC.MaxGeneration, GCCollectionMode.Forced, true);
GC.WaitForPendingFinalizers();
GC.Collect(GC.MaxGeneration, GCCollectionMode.Forced, true);
As you can understand reading this code, they are tries and the latest solution was changing the testing engine.
If your app is not too busy you could try to lock the db using a different mechanism (for example using a lock file). This is not really different from new DbContext() retries.
In late '90s I remember I had an issue related to disk sharing OS (I were using Novel Netware). Actually I have not experience in using mdb files on a network share. You could try to move the mdb on a folder shared with Windows
Actually I use Access databases only for tests. If you really need to use a single file database you could try other solutions: SQL Lite (you need a library, also this written by me, to apply code first https://www.nuget.org/packages/System.Data.SQLite.EF6.Migrations/ ) or SQL Server CE
Use a DBMS Server. This is for sure the best solution. As the writer of JetEntityFrameworkProvider I think that single file databases are great for single user apps (for this apps I suggest SQL Lite), for tests (I think that for tests JetEntityFrameworkProvider is great), for transfering data or, also, for readonly applications. In other cases use a DBMS Server. As you know, with EF, you can change from JetEntityFrameworkProvider to SQL Server or to MySql without effort.
You went wrong at the design stage: The MS Access database engine is unfit for ASP.Net sites, and this is explicitly stated on multiple places, e.g. the official download page under details.
The Access Database Engine 2016 Redistributable is not intended .... To be used by ... a program called from server-side web application such as ASP.NET
If you really have to work with an Access database, you can run a helper class that retries in case of common errors. But I don't recommend it.
The proper solution here is using a different RDBMS which exhibits stateless behavior. I recommend SQL Server Express, which has limitations, but if you exceed those you will be far beyond what Access supports, and wont cause errors like this.
I am using BizTalk 2013 version. I am facing an issue. I have a simple orchestration: I do poll from a SQL database every 30 seconds and then I have my message called PollingMessage. Then I need to transform this message into a new one (TestMessage) with a mapping. After this transformation I need to send my new message TestMessage to a port (TestPort) and then the old message PollingMessage to another port (SaveMessagePort). I built the project, deployed it and then I done the bindings through Administration Tool. When I start the application I successfully see my PollingMessage to the folder bound to SaveMessagePort but I can't see the TestMessage.
I don't understand why. Can you help me?
Ok, the problem is solved. There was something wrong with my schema, now everything is working like it should.
I am trying to do a couple of things within Cognos:
Load Framework Manager and view/modify SQL behind existing models and create new models
Modify existing reports through Report Studio via Cognos Connection
I was given an account on the Cognos application server and I installed Framework Manager. I was given the gateway URL and dispatcher URL from the System Admin and then transferred all of the project files to the server so that I could load the project in question. I'm able to open the .cpf file; however, when going into any models, I get the error:
Unable to access service at URL:
https://xxx.cognos.xxx.xxx:443/ibmcognos/cgi-bin/cognos.cgi?b_action=xts.run&m=portal/close.xts
Please check that your gateway URI information is configured correctly and that the service is available.
For further information please contact your service administrator.
I then contacted the system admin and he indicated that the URL was correct.
Furthermore, now when I try to access Cognos Connection (which worked fine last week), I receive the error:
CM-REQ-4159
Content Manager returned an error in the response header. The error "cmAuthenticateFailed CM-CAM-4005 Unable to authenticate. Check your security directory server connection and confirm the credentials entered at login." can be found in the response SOAP header.
The odd thing is, another member of my team receives this error:
AAA-AUT-0016:
https://xxx.cognos.xxx.xxx/ps/images/space.gif
https://xxx.cognos.xxx.xxx/ps/images/space.gif
https://xxx.cognos.xxx.xxx/ps/portal/images/msg_error.gif
The function call to 'Method.invoke(cmServiceInstance, queryRequest)' failed.
https://xxx.cognos.xxx.xxx/ps/images/space.gif
DetailsExpand:
CM-SYS-5192 An error occurred with Content Manager.
I've done some research (I'm not really familiar with Cognos or even networking) and found that these errors (the ones that I receive) are usually received when trying to run a single report; however, I can't even access FM models or Cognos Connection in general. I also don't understand how we can receive 2 different errors when accessing the same URLs from the same network.
Any guidance would be greatly appreciated. We are using Cognos 10.2.2.
http://www-01.ibm.com/support/docview.wss?uid=swg21624136
One possible reason is that the user does not have the required "Import relational metadata" capability.
Or maybe it is something to do with the registry
Note: Make sure you backup the registry before making any changes.
see http://www-01.ibm.com/support/docview.wss?uid=swg22015730
Open cmd and type "regedit".
Navigate to [HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main\FeatureControl.
Right click "BMT.exe" = dword:00002af9.
Delete.
Re-launch Framework Manager.
I'm making a program in flash builder 4.5 using WebOrb 4 (which is fantastic, I might add). When I go to deploy, however, it gives me this error:
>There was an error during model deployment for xxxxProgram.
>
>The server returned the following message:
>
>Unable to contact the RDS Server "Data Services on Tomcat (localhost)."
>
>Connection refused: connect
>
>Do you want to continue launching your Flex application?
I've poked around online for a solution, but for the most part I either don't understand them (forum grammar can be somewhat obtuse) or the answer in the post doesn't apply.
Any ideas?
the message that you received was thrown by the flash builder and the following part is quite confused:
"Unable to contact the RDS Server "Data Services on Tomcat
(localhost).""
Most likely, the root of the problem is the incorrect server address in your configuration. The WebORB RDS servlet (you are using WebORB for Java, aren't you?) is mapped to the /rds.wo url, so first of all I would recommend to check if the RDS servlet is up. If so, you should verify is your URL from project settings matched to you actual url where WebORB is running .
Additionally, please have a look on the WebORB plugin documentation step by step just to verify if everything is OK. The documentation is available here
Finally, if you will find nothing, please let me know the version of WebORB that you are using.