Access Denied error when trying to connect to Firebird in Visual Studio
I recently have it working that, within Visual Studio, I can see Firebird as a data provider.
The project I am working on I am trying to get the embedded version of Firebird working to use in my c# program
Howe开发者_StackOverflow社区ver, when I go to Tools/Connect to Database Choose firebird Data source I enter the following
Data source: Firebird Data Source (.net framework data provider for firebird) Data Source: is blank Data Source Port: 3050 Dialect: 3 charSet: NONE Database: path to my fdb file Server Type: Embedded user: username I setup password: password I setup role: is blank
when i click test connection, it immediately pops up that access is denied.
Any ideas on what might be causing this?
Thanks for the help.The Embedded edition of the database open the database file(s) in exclusive mode (DenyRead, DenyWrite), the server edition do the same thing.
That's by design, there's no way of coordination between two different database processes to allow to open that file and perform read/write operations successfully in a concurrent environment. If you want to allow different processes access to the database, you must do it connecting to a server edition of the Firebird product.
This is true also for your development environment. If you connect your IDE to the database using embedded, then execute your application using also embedded, the application will get an access denied error, because the file will be opened by the IDE. As you may know, the IDE and your application are, in fact, different processes.
Other possible scenario is when you're working with this database from FlameRobin or any other tool (using the server edition or the embedded one) and then you try to open the connection from the IDE using the embedded edition.
Because of that, using the embedded edition in the development environment is a bad idea.
What I do is always use a local server there. That way, I can connect my IDE database tools to the database (rarely, but sometimes I do that), any other tool, like isql, IBExpert, FlameRobin, I can maintain open connections from my project and run to test/debug without problems.
Then, if the application will use the embedded version in production, I switch to that version during the test/Q&A phase, and of course, on production.
I'm not using Firebird from Visual Studio or .NET, so I'm not sure what's the meaning of the Server Type: Embedded
parameter, or how the driver chooses between server and embedded, but whatever it is, you have to change it only in your release versions, while using server in debug versions.
Now, I must confess, I lie at the beginning of this answer, in fact using classic server, there are several processes (one for each connected client) accessing the database. I'm not sure how they share's access to that file between different process (maybe there are a reader/writer process, I don't know and, for now, I really don't care), that's another story and does not change what I say before.
I am guessing you are trying to connect using a FBConnection component, and the connection prompt looks like this
In that case what you call "Data Source" and tell us that is blank should point to localhost for an embedded database. Check the link I provided for more information.
If you are not using a FbConnection then please provide some more information about the connection component and connection string.
EDIT
Reading the information you add in your comments it seems you are trying to establish a connection to Firebird using ADO.NET (can not test it since I do not have Visual Studio installed on this machine), which is concordant with what I supposed earlier.
When you configure a connection to a Firebird database you are constructing a connection string which is used by your connection components to know how to connect to the database (please note that this applies also to several other databases when configuring the connection).
You can find more information about connection strings here and specifical to Firebird here.
As far as I know Firebird can be accessed from .NET in two ways:
Using ADO.NET: In this case you need to set Data Source to localhost. I think this is your case.
Using ODBC through .NET: In this case the connection looks very different. You can check it at the links I provided but I doubt that applies to your case.
So, in short version, please try to set "Data Source" to localhost.
HTH
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