Connection String in c# - c#

I am trying to connect to a database with my connection string and recieve the following error when trying to connect to the database. For intergrated Security I user SSID so I don't have to enter a username and password. Also, the database resides on the same machine and was created inside VS2010. I can connect to the db without a problem using the SqlDataSource, but I am looking to start writing my own connection strings.
protected void btnUpdate_Click(object sender, EventArgs e)
{
string source = "server=(local)" + "integrated security=SSPI;" + "Connect Timeout=30; " + "database=Name";
SqlConnection conn = new SqlConnection(source);
conn.Open();
conn.Close();
}
The Error I get is this:
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)

Try the following syntax as connection string:
string source = "Data Source=Server Address;Initial Catalog=Database Name;Integrated Security=SSPI;";
Where Server Address should be localhost or .\SQLExpress
Hope thats correct. I have'nt installed a vs for testing

You are missing a ; after the server name.
Why are you concatenating all the parts of the connection string if they do not change? It makes it more difficult to read.
Try this:
string source = "server=(local);integrated security=SSPI;ConnectTimeout=30;database=Name";

You need a semicolon after (local)
string source = "server=(local);" + "integrated security=SSPI
I notice you tagged the question with asp.net
by default asp.net runs under a system account, when you are using integrated security then that account is trying to access your database, it probably doesn't have permission.
Take a look here for some information.

I would recommend you to use the SqlConnectionStringBuilder: http://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqlconnectionstringbuilder(v=VS.100).aspx
That will probably make it easier.

To connect to SQL Server from C#.NET, you need to create a connection string such as below:
private SqlConnection connection;
private string connectionString =
#"Server=(local);Database=Embedding_SQL_Test;User ID=sa;Password=123";
connection = new SqlConnection( connectionString );
Next, you use the SqlConnection object created above to create a 'SqlCommand', as shown below:
SqlCommand cmd = new SqlCommand( "select * from Customer where CustomerID = #Cid",
connection);
The SQL query shown here can be replaced by a SELECT, INSERT, UPDATE queries etc.
Next to execute the SQL queries in the database, you use the following methods:
ExecuteReader - to execute SELECT queries
ExecuteNonQuery - to execute INSERT, DELETE, UPDATE, and SET statements.
This is a very short description of how to connect to SQL Server database from C# and execute SQL queries in the database.
For details about the connection string, the methods and their parameters check the following link: ( http://www.shahriarnk.com/Shahriar-N-K-Research-Embedding-SQL-in-C-Sharp-Java.html )
Here you will also find details about how to pass parameters to the SQL queries as well as calling stored procedures and much more.

Related

error connection to database c#

I'm trying to connect to a database from VS2017
var str = str1.ConnectionString =
"Data Source=141.*****.199;" +
"Initial Catalog=****;" +
"User id=***;" +
"Password=****;";
using (SqlConnection conn = new SqlConnection(str))
{
try
{
conn.Open();
var text = "SELECT * FROM Users u WHERE u.Id=76769";
...
}
catch (Exception e)
{
return req.CreateResponse(HttpStatusCode.OK, e.ToString());
}
and get error
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.
It's azure function. If I set this connection from LogicApp, then there are no errors.
Why the connection does not work from the azure-function?
can someone help. Functions refer to the database not with only ip , which are listed on the portal. They have several variants. And on the portal these addresses do not look, only through https: //resources.azure.com. And yes, you just need to specify in the firewall all valid values
I am connecting to an SQL DB from Azure Function, and I noticed a little difference in connection string that I am using.
Pls try and see if it works for you:
"Server=tcp:141.*****.199,1433;Initial Catalog=****;User ID=*****;Password=*****;"
1433 - is the default MS SQL port number.

Oracle connection with port, service name, and database from C# (ORA-12514

I'm new to Oracle. Trying to connect C# windows app to an Oracle database but can't seem to establish a proper connection. Keep getting exception: "ORA-12514: TNS:listener does not currently know of service requested in connect descriptor". I have to specify the port, service name, and database name in the connection string because the service id has access to multiple databases. I know that the values in the string are valid (valid server, valid serviceid, valid username, password, etc) because I have a third-party tool that is able to connect using the same parameters from a wizard. I've tried a lot of different ways to format the connection string but I always get the same 12514 error. In the code example, you'll see three formats (cxn, cxn2, and cxn3), I've tried each of them but get the same error.
string cxn = "Data Source=(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=MyServerName)(PORT=MyPortNumber))" +
"(CONNECT_DATA=(SERVICE_NAME=MyServiceId)));User Id=MyUserName; Password=MyPassword;";
string cxn2 = "DATA SOURCE=MyServerName:MyPortNumber/MyUserName;" +
"PERSIST SECURITY INFO=True;USER ID=MyUserName; password=MyPassword; Pooling = False;";
string cxn3 = "DATA SOURCE=MyServerName:MyPortNumber/MyServiceId;" +
"PERSIST SECURITY INFO=True;USER ID=MyUserName; password=MyPassword; Pooling = False;";
using (OracleConnection conn = new OracleConnection(cxn3))
{
string sqlSelect = "SELECT * FROM PERSONS";
using (OracleDataAdapter da = new OracleDataAdapter(sqlSelect, conn))
{
var table = new DataTable();
da.Fill(table);
if (table.Rows.Count > 1)
Console.WriteLine("Successfully read oracle.");
}
}
Again, I've used MyServiceId in the third-party tool's wizard and I connect just fine and select my database. I'm using Oracle.ManagedDataAccess.Client. I consulted a number of articles online including Oracle's guidance in section "Getting Started with ODP.NET, Managed Driver". How can I get the driver to recognize the valid service id and then also accept the database name? Any guidance is appreciated. Thanks.
Well I wish I had a more definitive explanation but as it turns out the code from my original question works NOW using the connection string defined in variable "cxn". I ran it many times before with no success, so my only guess is that the DBA changed something or rebooted the server since initial configuration.

Querying a website database from a C# console application

I'm trying to write a simple app in C# that will query a database available to the public located at https://newswire.theunderminejournal.com/
They give an example located at https://newswire.theunderminejournal.com/sample2.php
As far as I know, the server I'm trying to connect to is "newswire.theunderminejournal.com" and the database is "newsstand".
This gives me a string of:
string connection_str ="Server=newsstand.theunderminejournal.com;Database=newsstand";
My code looks like this:
xData = "Unable to connect to database.";
string server = "'newswire.theunderminejournal.com'";
//string server = "45.75.164.122";
string database = "'newsstand'";
string connection_str = string.Format("Server={0};Database={1};", server, database);
Console.WriteLine(connection_str);
SqlConnection connection = new SqlConnection(connection_str);
try
{
connection.Open();
xData = "Connection established!";
}
catch(Exception e)
{
xData = e.Message;
}
connection.Close();
connection.Dispose();
This results only in an error message:
"A network-related or instance-specific error occured while not
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've pinged the server, getting an IP address at 45.79.164.122 and no issues at all pinging it.
Is there something obvious I'm missing here? I'm brand new to C# so if there is another/better way of doing this, I'd appreciate it!
Thanks.
You cannot create a SqlConnection to a mySQL database, which is why the error message refers to "… establishing a connection to SQL Server.".
You need to use a MySqlConnection instead, which you get when you install Connector/Net - which you can download from Oracle here

Error connecting to SQL server through string, not recognising user name or password

the problem I am having is connecting to an account on my sql server (2005) from an ASP.NET application.
Ive tried using the default sa login and users ive created already also the setting of the sql management studio are set to mixed properties, I have the string connection in the webconfig as well but also doesnt work.
c# code
//string conStr = ConfigurationManager.ConnectionStrings["SQLConnectionString"].ConnectionString;
string conStr = #"server=JAMES-PC\SQLEXPRESS; database=projectDB; uid=james; password=password;";
string query = "SELECT [TaskID], [Task], [Start Date] AS Start_Date, [End Date] AS End_Date, [Priority], [Time Allowance] AS Time_Allowance, [Details], [Catagory] FROM [schedulerData0]";
SqlDataAdapter dataAdapt = new SqlDataAdapter(query, conStr);
DataTable table = new DataTable();
dataAdapt.Fill(table);
GridView1.DataSource = table;
GridView1.DataBind();
The error message I receive is:
Login failed for user 'james'. The user is not associated with a trusted SQL Server connection.
Any help appreciated
James
Your SQL SERVER configured for Windows Only connections and you current windows user not associated as trusted. Try to configure your SQL SEREVR to accept Mixed Mode connections.
Try this,I'm not sure but hope it will work-
<connectionStrings>
<add name ="conStr" connectionString ="Initial Catalog = projectDB;
Data Source =JAMES-PC\SQLEXPRESS; User Id=james;Password=password;"/>
</connectionStrings>
try mapping projectDB to user:james. open SQL Server Management Studio, select Security - Logins, double click user:james, select page:User Mapping, check projectDB.
Please try the following format If It is Sql Server user mode,
ConStr = "Server=JAMES-PC\SQLEXPRESS;Database=projectDB;User Id=james;
Password=password;"
if you are trying to connect using windows,
then you must provide Trusted Connection = true

Connecting to SQL Azure with ADO.NET

Hi I try to connect to a SQL AZURE DB with ADO.NET.
Here is my code:
private static string userName = "<**#********>";
private static string password = "<********>";
private static string dataSource = "<******.database.windows.net>";
private static string databaseName = "<******>";
public void Save()
{
SqlDataReader queryResultCloud;
string queryString = "select * from tblScan";
SqlConnectionStringBuilder connString2Builder;
connString2Builder = new SqlConnectionStringBuilder();
connString2Builder.DataSource = dataSource;
connString2Builder.InitialCatalog = databaseName;
connString2Builder.Encrypt = true;
connString2Builder.TrustServerCertificate = false;
connString2Builder.UserID = userName;
connString2Builder.Password = password;
using (SqlConnection connection = new SqlConnection(connString2Builder.ConnectionString))
{
SqlCommand command = new SqlCommand(queryString);
command.Connection = connection;
connection.Open();
queryResultCloud = command.ExecuteReader();
connection.Close();
}
and I get next error:
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)
Your code seems to be correct. One thing to try is to set TrustServerCertificate to true, and see if it works. Note it is recommended to set this property to false when Encrypt is set to true. But there’re reports that combination cause connection issues. I would like to suggest you to check http://www.wadewegner.com/2010/08/using-the-trustservercertificate-property-with-sql-azure-and-entity-framework/ for more information. In addition, check again if you have configured SQL Azure firewall to allow connection to your local machine. If you’re behind a proxy, it is needed to add your proxy’s IP address to the firewall exception.
Best Regards,
Ming Xu.
You're likely behind a proxy that doesn't allow outbound connections to port 1433, which is the only port you can use with SQL Azure:
The Windows Azure SQL Database service is only available with TCP port
1433. To access a SQL Database database from your computer, ensure that your firewall allows outgoing TCP communication on TCP port 1433.
I'm in this situation as well, and the most promising / challenging solution appears to be this port bridging application technique, but the solution itself is dated and needs an older version of VS than I have installed, so I'm looking at some other alternatives.

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