I've made a code that create the database automatically in the folder where the software is executed. The DB was created succesfull, but when I create the object for the connection this exception is displayed:
System.Data.SqlClient.SqlException (0x80131904): There was a network error or specific instance while trying to establish 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) ---> System.ComponentModel.Win32Exception (0x80004005): Can not find the file specified
on this line:
con.Open();
but the problem I think is on this declaration of the connection:
static SqlConnection con = new SqlConnection(
"Server=localhost;Database=AppDB.sqlite;");
What am I doing wrong?
UPDATE Details:
SqlCommand command = new SqlCommand(#"INSERT INTO Team (name,code, shortName, squadMarketValue,
crestUrl, link_self, link_fixtures, link_players, caption) VALUES (#name,
#code,#shortName,#squadMarketValue,#crestUrl,#link_self,#link_fixtures,
#link_players,#caption)", con);
How you can see I'm using parametizer query, and if I use this object:
static SQLiteConnection m_dbConnection = new SQLiteConnection("Data Source=SoccerForecast.sqlite;Version=3;");
the con variable is underlined in red, an the compilers tell me:
it is not possible to convert SqliteConnection in SqlConnection
Your connection is wrong. You didn't specified the kind of database you're trying to connect to in your question. There's a mention of SQLite while your are using an sql connection object. The sql connection object is for connection to the ms sql server database. If you really want to connect to an ms sql server database, you'll need to change the connection string to provide a username / password or a Trusted_Connection=True to use your windows account.
However, if the database you are trying to connect to is an SQLite DB, you will have to use a different connection object. This and this SO question has answers about available libraries and examples that will explain how to create a connection to a SQLite database.
The site connectionstring.com is also a good resource when you need to generate a connection string.
Related
Hi I am trying to connect to a local SQL Server Compact database (.sdf) in a Windows forms project and have been facing this problem for quite some time. I am not allowed to use datasets for the project, all the queries and connections are written in the application.
System.Data.SqlClient.SqlException
A network-related or instance-specific error occurredwhile 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)
Code:
SqlConnection _Connection = new SqlConnection(ConfigurationManager.ConnectionStrings["restaurant"].ToString());
SqlCommand _Command = _Connection.CreateCommand();
_Connection.Open(); // <- throws exception
To connect a Sql Server Compact you need a different set of classes contained in the namespace SqlServerCe (SqlCeConnection, SqlCeCommand and so on....)
SqlCeConnection _Connection = new SqlCeConnection(ConfigurationManager.ConnectionStrings["restaurant"].ToString());
SqlCeCommand _Command = _Connection.CreateCommand();
_Connection.Open();
of course, you need to reference the assembly that contains the above mentioned classes.
System.Data.SqlServerCe.dll (ADO.NET provider)
and add the using statement
using System.Data.SqlServerCe;
I have some problems with connecting to my local DB using c# System.Data.SqlClient.
Information:
DB parameters: Name:baza Host:localhost Instance:baza Port:3306 Schema:world
My connection string: #"server=localhost\baza;password=pass;User Id=root;database=world;Persist Security Info=True"
using: c#, System.Data.SqlClient, MySQL Workbench
firewall off
succesfull conection with JDBC, so server is working
JDBC parameters:
String url = "jdbc:mysql://localhost:3306/";
String driver = "com.mysql.jdbc.Driver";
String dbName = "world";
String username = "root";
String pass = "pass";
Problem:
when I use conn.Open(); this happen => (provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified)
Tried:
server=localhost then it gives => error: 40 - Could not open a connection to SQL Server
many other stupid combinations like server=baza
http://blogs.msdn.com/b/sql_protocols/archive/2007/05/13/sql-network-interfaces-error-26-error-locating-server-instance-specified.aspx
ASP.NET beginner question: How to get rid of this error?
Connection to freesql.org server also failed
I have no idea what to do... Sth is probably with server name.
EDIT:
code:
string connstr = #"Data Source=localhost\baza;password=qspass;User Id=root;"+
"Initial Catalog=world;Persist Security Info=True";
Console.WriteLine(connstr);
SqlConnection conn = new SqlConnection(conbuild.ConnectionString);
conn.Open();
Console.WriteLine("YO!");
Some more code...
Never reached YO! :P
I suppose I should put my answer in the answer section, rather than a comment :)
I see from your JDBC connection string that you are using MySQL rather than SQL Server.
The System.Data.SqlClient namespace is the.NET Framework Data Provider for SQL Server, not MySQL.
If you are using MySQL, you will need to use the MySQL ADO.NET driver available here:
Download Connector/Net
We have a "legacy" application, which uses ODBC connections to an underlying database, which can be Access, Oracle or SQL Server. For unit (or, perhaps more properly, "integration") test purposes, I'd like to hook up a SQL Server 2012 LocalDB instance. However, I cannot figure out a correct ODBC connection string to use.
I have tried:
[TestMethod]
public void OdbcConnectionToLocalDb()
{
string connectionString = "DRIVER=SQL Server Native Client 11.0;Trusted_Connection=Yes;SERVER=(localdb)\v11.0;Description=LocalDB;";
using (OdbcConnection connection = new OdbcConnection(connectionString))
{
using (var command = new OdbcCommand("select * from Person", connection))
{
connection.Open();
// ...
}
}
}
However, when the connection is opened, the following exception is thrown:
System.Data.Odbc.OdbcException: ERROR [08001] [Microsoft][SQL Server Native Client 11.0]Named Pipes Provider: Could not open a connection to SQL Server [67].
ERROR [HYT00] [Microsoft][SQL Server Native Client 11.0]Login timeout expired
ERROR [08001] [Microsoft][SQL Server Native Client 11.0]A network-related or instance-specific error has occurred while establishing a connection to SQL Server. Server is not found or not accessible. Check if instance name is correct and if SQL Server is configured to allow remote connections. For more information see SQL Server Books Online.
Is it possible to connect to a SQL Server 2012 LocalDB via an ODBC connection/driver? Is it possible to connect to a specific file?
[EDIT]
Garrett points out it is possible, great. I must have the connection string wrong, so my question really should be: what should the connection string be?
You need to specify your connection string like this:
Provider=SQLNCLI11.1;Integrated Security=SSPI;Persist Security Info=False;Initial Catalog=TestDB;Data Source=(localdb)\v11.0
The main thing I think is that you reference it as a data source rather than server.
Yes, it's possible. Make sure you install the latest driver: SQL Server Native Client "Denali" (for ODBC and OLE DB).
Look here for more info:
http://blogs.msdn.com/b/sqlexpress/archive/2011/07/12/introducing-localdb-a-better-sql-express.aspx
I've got an SQL server and database setup on an external server (let's call the domain name "hello.com" for the purposes of this), and I want to connect to this server via a C# program. So far I have this (All server/database details are different to the real ones):
private static void SetupSQL()
{
string connectionString = "server=hello.com; database=db1; uid=user1; pwd=xxxxx;";
connection = new SqlConnection();
connection.ConnectionString = connectionString;
try
{
connection.Open();
Console.WriteLine("Connected");
}
catch (Exception e)
{
Console.WriteLine(e.Message.ToString());
}
}
This is giving me an error 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: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)
I have checked all the connection string, and I am allowed remote access, as I have SQLWorkbench open querying the database right now on the same computer.
Any ideas?
You'll need the MySQL driver:
http://dev.mysql.com/downloads/connector/net/
You can then use the the MySqlConnection connection class to connect.
MySqlConnection connection = new MySqlConnection(connectionString);
http://www.codeproject.com/Articles/43438/Connect-C-to-MySQL
You can't use SqlConnection object to connect to MySQL database, you should use MySqlConnection instead after you import its dll
Im facing problem with database connection on windows Application Database Connection c#... here is my connection ,,, PC2 is PCNAme
private static SqlConnection con = new SqlConnection(
"Data Source=PC2\\SQLEXPRESS; Initial Catalog=Database1;Integrated Security=True"
);
when I run the form I get this unhandled exception on con.Open();
sqlException was unhandeled:
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)
hope some one can help Im trying to solve it for many hours but not working.
Check this trouble shoot steps on MSDN:
The SQL Server client cannot connect to the server MSDN
And much better if you separate your connection string to your ado.net sql connection.
private const string _thisConnectionString = "Data Source=PC2\\SQLEXPRESS; Initial Catalog=Database1;Integrated Security=SSPI";
Use the "Using" Statement ensure that you always close your Connection.
Best Practices for Using ADO.NET MSDN
using (var conn = new SqlConnection(_thisConnectionString))
{
SqlCommand cmd = conn.CreateCommand();
cmd.CommandText = "Your SQL Query STuff";
conn.Open();
}
Regards
Try This:
private static SqlConnection con = new SqlConnection(
"Data Source=PC2\SQLEXPRESS; Initial Catalog=Database1;Integrated Security=True"
);
Go to SQL Server Configuration Management -> Click on SQL Server Services
Verify SQL Server and SQL Server browser both are running. you can see a Greed play button there. if it's not running right click on the service which shows Red, go to properties, Click Built in Account and Press Apply then OK, There try to start by right click.