I am developing a winforms application in Vb.net
when i try to add a tableadapter to an existing dataset I am receiving the error:
Failed to open a connection to the database.
"An attempt to attach an auto-named database for file ###Filelocation### failed. A database with the same name exists, or specified file cannot be opened, or it is located on UNC share." Check the connection and try again.
This same dataset has 2 other tableadapters using the same dataconnection (as I am selecting the already existing dataconnection) which work fine
this connection is using application connection strings:
Data Source=(LocalDB)\v11.0;AttachDbFilename=|DataDirectory|\test.mdf;Integrated
server=localhost;user id=root;password=password;database=testuser;persistsecurityinfo=True
this error pops up every time I select the dataconnector on the first window that pops up.
Why is this happening
additional info:
The other 2 tableadapters were added to this dataset using a different computer
this is for a mysql connection
I found this post on the MSDN forum:
An attempt to attach an auto-named database ....\aspnetdb.mdf failed
One of the suggestions is as Mr. DonBoitnott correctly says, add User Instance=True;. But, there's also another suggestion posted by Luke A.
"For the record, not one single error message given to me during the course of trying to fix this was relevant to the actual problem. Upon first receiving "An attempt to attached an auto-named database..." I looked online for every suggestion I could find: use an absolute path to the MDF, reorder TCP/IP and named pipes in the server configuration, disable/enable UserInstance (depending on where you looked), change security settings, reconfigure authentication, give specific login credentials.
None of these worked. All of these led to different vague/ambiguous error messages, which led to another problem which required a solution which led back to the original error message... an endless loop of problems, completely unrelated to what was actually wrong.
_Also, posts about setting correct permissions on the App_Data folder are deceptive, as they imply the default permissions were not sufficient for SQL Express (in fact, they are). The whole point of this VS environment is that you can develop a web application and plop it right onto an IIS/SQLExpress setup and have it work. This makes the applications more portable (within IIS, of course) and secure. Of course, everything configuration-related has been obfuscated enough to make it several orders of magnitude more difficult than it has to be."_
So: Try prepend Initial Catalog=uniquenamehere to your connection string.
Though he says "... where 'uniquenamehere' is some name for your project.", try replacing uniquenamehere with the actual name of the database where the table exists.
the file is a .mdf file so it is a mssql file
my guess would be that as you stated you are using mysql the connection string has to be a tad different and therefore the Dataset can't connect to Mysql
Try adding User Instance=True; to the connection string.
Related
I know that similar topics have been already raised, but maybe there are some latest news or ideas?
I want to migrate Datazen users/sources/dashboards etc. to another server (production one) in a smooth way. I was trying to do that via backup/restore, but then I couldn't access the control panel on the target server. I received an error
401 unauthorized access.
Maybe I should change something in logs/config files on the destination server?
Any ideas? I would be grateful for any help!
I dont think there is a way to do this out of the box. However, the files are quite simple XML, so can be pointed at a different server if you know PowerShell (and work out the correct values from the server).
You will have to re-point the GUID, ServerGUID and ServerURI within the sources.xml file and then rezip (as .datazen). Providing you have your hubs set up the same, Datazen will then believe the file belongs to your prod environment and you will be able to publish
I have an MS Access split database and I'm trying to get it to work with the backend on a new, more secure drive on our network. I've used a UNC path for the backend location.
This database has been running without problem on another drive which is totally public to everyone in the company (~4k people, not secure) for about a year. We have a generic account for users to access the database throughout our factory and haven't encountered this problem before I tried to switch it to the new drive. I've contacted our IT department and they've given myself and all my user's accounts read/write access to the drive, but only I can run it.
Other user accounts get these problems...
All of my forms with objects bound to a table immediately throw a runtime error before even getting to Form_Load.
My userforms will run DLookup functions and execute message boxes but throw a runtime error when they go to execute a query.
I've tried using an 'On Error goto' to try and actually find the problem but it throws a runtime error before that.
I can't think at all what the problem might be. IT have told me I have the same permissions as the other users. Any suggestions on what to do?
In the front end of your DB you may have to change the path which links to the tables. The tables are in the back end of the database, which you have now moved and therefore changed the filepath. the frontend wont find them. You can delete the table links in the front end then use External data > import and Link > Access. In order to re-link the tables using their new filepath. You would then need to redistribute your frontend to the users.
I'm not sure if you have already done this, however, you haven't suggested so in your question. hope this helps, apologies if it was helpless.
I hope you have found an answer to this. I wanted to answer as well, because I had the exact same problem yesterday. It turned out that the location was referring other users back to the folder's shortcut name versus it's full length name (it is called the W drive on my computer and the K drive on theirs). I solved the issue by spelling out the name in full.
I would like to switch between running on a database on the server (the real database) and a local copy that I keep for testing in localhost.
I tried to switch between db#1 (server) and db#2 (localhost) by changing the definition of the connection string in app.config (I also restarted VS to make sure nothing hides in memory). A strange thing happens: on the one hand if I query the db through datasource/preview data (in VS'10) indeed it brings the data from db#2. But when I run the application is still grabs the information from db#1, although as far as I know the connection string appears only in app.config, so I do not even understand where does it take the information from in order to connect to db#1.
While we're on the subject, what would be the more elegant way to switch between databases ? ideally from a pull-down menu I would chose the data source. But can I switch the connection string in run time ?
Visual studio maintains its own database connection info, presumably from its own app.config file. This is completely independent of your solutions app.config.
Switching databases as you suggest is relatively easy. Put 2 connection strings with different names in your app.config. Use a variable to hold the string you want and reference this wherever you are directly referencing the connection string now.
Just a little background: I am using Access 2010 to create forms and VBA code in an Access 2003 format database. For some reason, Access 2007 format databases always corrupt on me when I make changes and save them with a particular group of objects, but that's for another discussion.
When writing VBA code in this Access 2003 database, any time my code breaks (via breakpoint or an unhandled error) and I make a correction, Access tells me that it can't save back to the database because another user has it open. However, I am the only user working on the database; this is a local copy of the database and it's sitting on my desktop.
The LDB file can't be deleted because Access is using it. When I first load the database, I see my machine name and "Admin" when opening the LDB in a text or hex editor. After a break, I see that plus a duplicate entry, but this time around "admin" has a lower-case "A."
Closing the database and reopening it fixes the problem but makes it needlessly cumbersome to debug my code. Anyone else encounter this issue and/or have a fix for it?
It might be helpful to know what your code is doing when this happens. Certainly that's not normal behavior. For instance, are you opening another database with New Access.Application? Are you using ADO or DAO to access records in the database with a connection string?
There are no external connections to the database at all.
It may not matter if there are external connections to the database if you are using a connection string to connect to the open database; not sure but that may be seen as an external connection... you may want to use CurrentDB for DAO, or CurrentProject.Connection as your ActiveConnection for any ADO queries.
I am assuming that this problem persists through reboots; but for the sake of argument, try closing out Access and going to the task manager to make sure you have no other instances of MSAccess.exe running. You might even try closing all Office products and/or making sure that Access is the only Office product running. I have seen some weird conflicts between Microsoft Communicator and Outlook; so it's not entirely out of the question for Access to have issues with another MS product.
You may also want to check the size of the database to make sure it's not exceeded 2GB. That causes the infamous "Invalid parameter" error; perhaps it might be causing this as well.
With no other details about how your program works, we may only be able to offer generic advice like this.
I have discovered a way to cause the problem discussed above (and thereby to correct it). Turns out if you create a database object and set it to the current database, you get this problem.
That is,
dim cdb as database
set cdb = currentdb
From this point on, you're cooked.
Instead, figure a way around this by possibly using currentdb directly or not using it at all.
This worked for me.
In your VBA Try checking that all your open Connections to the database are closed. Until the connection is open the LDB fill will be there.
Same symptom of not being able to save form or code mods after application had started. I found a workaround today! In the startup of my first form of the app, I had issued a "DAO.DBEngine.SetOption dbMaxLocksPerFile, 20000". Commenting this statement removed the problem. I did no further testing, but FYI, the DBEngine call was before any reference or attempt to use CurrentDB(). Also the current default on my Access 16 install is 9,500.
I thought I might answer here, since I stumbled upon this question while having a similar issue. Essentially, it boiled down to this: I could either edit forms, VBA, etc. or edit information in the local database (which I'm using as a cache) with currentDB. I also have a backend database, but the locking was clearly on the frontend database.
The solution ended up being weird, but stupidly simple. When the frontend starts up, I have it immediately create a connection to the backend using OpenRecordset (and similarly to you, that backend was still on my own computer for testing purposes). I tried temporarily disabling that code, and suddenly it wasn't an issue anymore. And it turns out, once I call currentDB, I can then call OpenRecordset to open the connection to the backend, and suddenly it isn't a problem anymore.
Tl;Dr: if you're calling OpenRecordset somewhere in your code to connect to a backend, be sure to call something like set db = currentDB beforehand, then everything works. (That is, probably until I publish this answer and Access then decides it doesn't want to anymore).
Why this fixed it is beyond me, someone with more knowledge can maybe answer that.
The solution:
options > current database > click enable -track name auto correct info
I have a nice little Linq2SQL project however when deployed the database is on another server. I keep getting a named pipe error that the remote server doesn't exist - yet it does, it has Named Pipes enabled (protocol + surface) SQL 2005. TCP connections work fine.
I've tried setting the library in the connection string to a TCP one, I tried forcing TCP in the server name however Linq is always and only using Named Pipes and just won't work.
Any idea how to force Linq2SQL to use TCP/IP only, if possible?
thanks
My guess is that you are not setting the connection string to None on the DBML designer file which is creating the typed data context for you. Set the connection string to None (make sure nothing on the designer is selected) and then pass in the connection string manually, to assure that you have complete control over it.
As noted in the comments, you can't set the connection string to none.
In this case, there is still an overload of the typed DataContext which takes a connection string as a parameter. I would recommend using a hard-coded one first to see if it works. If it does, then you know it is the resolution of the item from the config file. Otherwise, you know to look at the connection string itself.
Also, if it is a problem with resolution in the config file, I usually place this in my connection string section FIRST to clear entries from the machine.config file:
<clear />
How about changing the protocol order in the SQLConfiguration manager or using the command tool, cliconfig on the client and changing it there.
I've seen this happen when (any of these):
The SQL client version isn't the one you expect
Windows Authentication is being used, often unintentionally
The connection information you provide doesn't match with the server's own name. (That is, select ##server_name doesn't return the same as the NETBIOS name. Fix using sp_dropserver and sp_addserver)
Sometimes reinstalling MDAC on the client machine helps, apparently because the driver looked like it was there but wasn't fully working.
Hope this helps...