I have the following code to connect to a sql server compact edition 2008:
private SqlConnection sqlConn;
public void createConnection()
{
String connectionString = #"Data Source=C:\Projects\somefile.sdf;Persist Security Info=False";
sqlConn = new SqlConnection(connectionString);
sqlConn.Open();
}
However, I keep getting the following error when sqlConn.Open() is executed:
"A network-related or
instance-specific error occurred while
establishing a connection to SQL
Server. The server was not found or
was not accessible. Verify that the
instance name is correct and that SQL
Server is configured to allow remote
connections. (provider: SQL Network
Interfaces, error: 26 - Error Locating
Server/Instance Specified)"
Does anyone have any ideas what the problem might be? I can create a connection to the db in the database explorer but it doesn't seem to work in code.
The Sql* classes in System.Data.SqlClient can only be used to connect to a regular SQL Server instance.
To connect to a SQL CE database, you need to create a SqlCeConnection object in System.Data.SqlServerCe.dll.
Is the sdf file in the same directory as the executing application?
How to specify the location of the SDF file
Often times the .SDF database is not running in the current directory so it becomes necessary to programatically set the path to the SDF file. This is an example (.net C#) on how to do this when the SDF file is located in the same directory as the executing application.
Data Source=" + (System.IO.Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().GetName().CodeBase) + "\\MyData.sdf;Persist Security Info=False;
Source
Related
I have written an application that uses SqlClient and a local mdf database. However, it does not work on another machine (throwing an exception that the server cannot be run) and I assume this is because there is no SQL server installed? But I thought that using local database and SqlClient elimites the need for the server, something like the old SQL CE. Is that the problem?
EDIT Exception: System.Data.SqlClient.SqlException (0x80131904): A network-related or instance-specific error occurred while extablishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections
As for connection string, I keep the one generated by Visual Studio Express, just modify the path to use the app folder.
SqlConnection s = new SqlConnection(#"Data Source = (LocalDB)\MSSQLLocalDB; AttachDbFilename ="+ System.IO.Path.GetDirectoryName(Application.ExecutablePath)+ #"\Database1.mdf; Integrated Security = True");
Is there a simple way how to rework this so that my app does not require SQL server installed? All I need is to have it use the local database file in its folder.
A developer friend and I could not get a connection string to work on my PC.
I'm calling to a local db instance which is Management Studio 2014 (one of the free editions).
It fails on connection.Open();
The Code is:
string conn = ConfigurationManager.ConnectionStrings["DatabaseConnection"].ToString();
IDbConnection connection = new SqlConnection(conn);
connection.Open();
App.Config is:
<connectionStrings>
<add name="DatabaseConnection"
connectionString="data source=MIKE-PC; initial catalog=dbname;integrated security =True"
providerName="System.Data.SqlClient" />
</connectionStrings>
The Error is:
An unhandled exception of type 'System.Data.SqlClient.SqlException'
occurred in System.Data.dll
Additional information:
A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)
There are many possible issues that you can check to correct this:
Make sure your database server is running: open run or shortcut Window + R, type services.msc, hit enter. Make sure the SQL Server (SQLEXPRESS) service is running.
Open your SQL Management Studio. Try to connect to your database from there to make sure your server name (data source) and database name (initial catalog) are correct.
Make sure your database can be accessed using Integrated Security. You can tell that it does if you can connect to your database using "Windows Authentication" from your MS SQL Server Management Studio.
Hope this help.
I'm working on C# .net application that needs to connect to a simple database. This database is btw in the same visual studio project and is called Playerdatabase.mdf.
In the application I want to connect to the database by using the following code:
string connectionString = "Data Source=(LocalDB)\v11.0;AttachDbFilename=C:\\Users\\User1\\Documents\\Visual Studio 2013\\Projects\\ProreactorTest\\ProreactorTest\\Playerdatabase.mdf;Integrated Security=True;Connect Timeout=30";
SqlConnection con = new SqlConnection(connectionString);
con.Open();
But when I try to run the application and when it calls the open() method I got the exception:
Additional information: A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL
Inner exception: can not find network path.
I looked at the path (by browsing to it) and it looks fine. I also read that disabling the firewall works, tried that but got the same exception.
Does anybody have a idea or suggestion? Any feedback is welcome!
Recently, I've made a simple website with a database (in an App_Data folder). I made a class file (in an App_Code folder) with the following method that will create a connection to the database:
public static SqlConnection ConnectToDb(string dbFileName)
{
string path = HttpContext.Current.Server.MapPath("App_Data/");
path += dbFileName;
string connString = #"Data Source=.\SQLEXPRESS;AttachDbFilename=" +
path +
";Integrated Security=True;User Instance=True";
SqlConnection conn = new SqlConnection(connString);
return conn;
}
When I need to open that connection, I get the following message:
A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified)
What I don't understand is that I used the -same- method in another website that I built over a year ago in Visual Studio 2010, where it worked fine.
I checked the path and it was correct, same with the database file name in the parameters.
What is wrong with the code or with VS's settings? Thanks in advance.
EDIT: Just tried to use (localDB)\v11.0 instead of .\SQLEXPRESS
and now I get this error message:
The user instance login flag is not allowed when connecting to a user instance of SQL Server.
You're getting that error because the (localDB)\v11.0 is already a user instance of SQL Server. When you were using the SQLEXPRESS SQL Server instance, well, it's not. So, just get rid of the User Instance=true on the connection string.
The following code gives an error during execution.
string connectionString = "Data Source=D:\\Base.sdf;Persist Security Info=False";
SqlConnection sqlConnection = new SqlConnection(connectionString))
sqlConnection.Open();
The error is:
A network-related or instance-specific error occured while establishing a connection to SQL Server. The server was not found or
was not accessible. Verify that the instance name is correct and that
SQL server is not configured to allow remote connections.
(provider:SQL network Interfaces, error: 26 - Error locating
Server/Instance Specified)
I tried SqlCeConnection instead of SqlConnection but, the compiler couldn't find the library with that class.
Please, help to solve this problem.
The OS : Windows 7
Tool : Microsoft Visual Studio 2010
Language : C#
Your database is a Sql Server compact edition one, you must use :
SqlCeConnection sqlConnection = new SqlCeConnection(connectionString);
Download the libs from here Microsoft SQL Server Compact 4.0
Add a reference to System.Data.SqlServerCe.dll to your project
Add this using directive using System.Data.SqlServerCe;
Use SqlCeConnection instead of SqlConnection