We Keep Coding

Cannot connect to SQL Server with Windows authentication from C#

I want to connect to SQL Server 2016 using Windows authentication.
I am using C# with this connection string
Server=192.168.1.12,14331;Database=master;Integrated Security=true;Timeout=30
or
Server=serversql\newinstance;Database=master;Integrated Security=true;Timeout=30
The error is a timeout connection.
When using connection with SQL Server authentication like this:
Server=192.168.1.12,14331;Database=master;User Id=***;Password=****;Timeout=30
everything is ok.
Source code C#
var constr = "<connection string>";
using (var connection = new SqlConnection(constr))
{
var command = connection.CreateCommand();
command.CommandType = CommandType.Text;
command.CommandText = "SELECT 1";
command.CommandTimeout = 0;
connection.Open();
command.ExecuteNonQuery();
}
But when I am using SQL Server Management Studio to check connection to the SQL Server instance with Windows authentication, it is ok. Using alias or Ip address does not help the error.
I don't understand why I get this error ...
Help me please! Thanks you everyone!
UPDATE:
If I use connection 1 with IP and port, there is an error:
Login failed. The login is from an untrusted domain and cannot be used
with Windows
UPDATE:
Instance SQL installed on other PC the same network LAN with My PC.
I'm checked Log Viewer on PC install instance SQL but no record log.

I'm not sure it works for you, but you can try it:
SqlConnection cnn;
public connect(){
string strConnect = #"Data Source=192.168.1.12,14331;Network Library=DBMSSOCN;Initial Catalog=master;User ID=****;Password=*****";
cnn = new SqlConnection(strConnect);
try
{
cnn.Open();
}
catch(Exception)
{
// connect failed
}
}
public void ExeQuery(string query){
// query="select * from tblA"
SqlCommand sqlCmd = new SqlCommand(query,cnn);
sqlCmd.ExecuteNonQuery();
sql.Dispose();
}

Can't Connect C# with SQL Server

I am trying to write a program which interacts with my SQL Server database. I am programming in C# on Parallels on my Mac and SQL Server is running via Docker.
But I just can't connect. I am just getting the same error every time I try.
I have already tried to allow the remote access on SQL Server with:
EXEC sp_configure 'remote access', 1 ;
GO
RECONFIGURE ;
GO
but this does not solve my problem.
Here is my C# code:
main Class
Database database;
public Form1()
{
InitializeComponent();
database = new Database("localhost\\MSSQLSERVER", "user1", "topsecret", "master"); // \
}
private void connect_button_Click(object sender, EventArgs e)
{
database.Connect();
}
Database class:
class Database
{
SqlConnectionStringBuilder builder;
SqlConnection connection;
public Database(string source, string userid, string password, string initialcatalog){
this.builder = new SqlConnectionStringBuilder();
this.builder.DataSource = source;
this.builder.UserID = userid;
this.builder.Password = password;
this.builder.InitialCatalog = initialcatalog;
}
public void Connect()
{
try
{
// Connect to SQL
Console.WriteLine("Connecting to SQL Server ... ");
this.connection = new SqlConnection(this.builder.ConnectionString);
connection.Open();
Console.WriteLine("Connected");
}
catch(SqlException sqle)
{
Console.WriteLine(sqle.Message);
}
}
}
And I am always getting this error:
Network-related or instance-specific error when connecting to SQL Server. The server was not found or can not be accessed. Verify that the instance name is correct and that SQL Server allows remote connections. (provider: SQL Network Interfaces, error: 25 - connection string invalid)

The MSSQLSERVER is the instance name of the unnamed, default instance on your machine - you must not use this in the connection string.
Instead, try this line of code:
database = new Database("localhost", "user1", "topsecret", "master");
Just specify no explicit instance name at all - just localhost (or (local), or .) for the current machine - that's all you need!

It was Problem with Parallels, because Paralles can not access to localhost. So i had to define the IP from Parallels in Visual Studio like this:
database = new Database("10.211.55.2", "user1", "topsecret", "Time");

azure connection string c#

I am trying to open connection with Azure SQL database. Tried creating usual connection = new MySqlConnection("Server=" + server + "Database=" + database + "Uid=" + uid + "Password=" + password); with every string variable ending with ; but yet it always fails to connect even if the data is correct. Tried to use given string for ADO.NET but then I am getting exception "keyword is not supported". I don't what else to actually.. Googled as much as possible but all solutions are quite the same and yet nothing works out for me :/

Firstly, azure databases don't use mysql. so using MySqlConnection() won't work.
instead use
SqlConnection connection = new SqlConnection(connectionstring);
Standard connection strings should be in the format
Server=tcp:[serverName].database.windows.net;Database=myDataBase;
User ID=[LoginForDb]#[serverName];Password=myPassword;Trusted_Connection=False;
Encrypt=True;
See https://www.connectionstrings.com/azure-sql-database/ for more options

var connectionString = #"Server=tcp:<dbname>.database.windows.net,1433;Initial Catalog=<databasename>;Persist Security Info=False;User ID=<userid>;Password=<password>;MultipleActiveResultSets=False;Encrypt=True;TrustServerCertificate=False;Connection Timeout=30;";
That's how I connect to my Azure SQL Database, works for me.

For MySQL In App you can use the fellowing code in c# to get the connection string:
static string getConnectionString()
{
#if DEBUG
string connectionString = "dbname=localdb;host=localhost:3306;user=root;pass=password;";
#else
string connectionString = Environment.GetEnvironmentVariable("MYSQLCONNSTR_localdb");
#endif
string[] options = connectionString.Split(";");
string database = options[0].Split("=")[1]; ;
string serverport = options[1].Split("=")[1];
string server = serverport.Split(":")[0];
string port = serverport.Split(":")[1];
string user = options[2].Split("=")[1];
string password = options[3].Split("=")[1]; ;
connectionString = $"server={server};port={port};database={database};user={user};password={password};";
return connectionString;
}

The standard .Net Framework provider format is:
Server=[serverName].database.windows.net;Database=myDataBase;
User ID=[LoginForDb]#[serverName];Password=myPassword;Trusted_Connection=False;
Encrypt=True;
Azure SQL Database is an SQL Server type database, not MySQL!

Have you followed Microsoft instructions?
https://learn.microsoft.com/en-us/azure/sql-database/sql-database-connect-query-dotnet-visual-studio
You have to create server-level firewall rule on azure too, to be able to connect.

No start database manager command was issued error

I have a DB2 expresss in my machine and I am able to query from the database using command window (after following two commands):
set DB2INSTANCE=db2inst1
db2 connect to tims user
Now, when I try to connect to the database from a C# console application, I am getting following errors with different connection strings.
Attempt 1
string connectionString = #"Provider = IBMDADB2; Database = TIMS; Hostname = localhost; CurrentSchema=db2inst1; ";
SQL1032N No start database manager command was issued. SQLSTATE=57019
Attempt 2
string connectionString = #"Provider = IBMDADB2; Database = TIMS; CurrentSchema=db2inst1; ";
SQL1031N The database directory cannot be found on the indicated file system. SQLSTATE=58031
What should be the correct connection string for this scenario?
CODE
string connectionString = #"Provider = IBMDADB2; Database = TIMS; Hostname = localhost; CurrentSchema=db2inst1; ";
OleDbConnection myConnection = new OleDbConnection();
myConnection.ConnectionString = connectionString;
myConnection.Open();

Do you have multiple DB2 instances running on your machine? You can get a list of instances that exist by executing the db2ilist command.
If you have to execute the set DB2INSTANCE=db2inst1 statement when you open a DB2 Command Window in order to connect to the TIMS database with the db2 connect to TIMS command, then you need to ensure that the environment for your C# application is configured the same way.
You can do this in a number of ways:
by setting the DB2INSTANCE environment variable before starting your application
Change the default DB2 instance on your machine by using the command db2set -g DB2INSTDEF=db2inst1 (** see note below)
Use a TCPIP connection string (as described by #Bhaarat) so that your application does not depend on the database catalog for the default instance
Note: Before changing DB2INSTDEF you may want to see what the current value is, by executing the command db2set -all and looking for DB2INSTDEF in the output. Also note that changing the default instance may affect other applications that run on your machine.

refer this url http://www.c-sharpcorner.com/uploadfile/nipuntomar/connection-strings-for-ibm-db2/
your connection string should be something like this
Provider=IBMDADB2;Database=urDataBase;Hostname=urServerAddress;Protocol=TCPIP;Port=50000;
Uid=urUsername;Pwd=urPassword;
in more you can refer this too
http://www.codeproject.com/Articles/4870/Connect-to-DB2-from-Microsoft-NET

My DB2 insatnce name is "db2inst1" and it was working fine when I used DB2 command window.
Now I made following settings and it is working fine now. :-)
Created a port in the C:\Windows\System32\drivers\etc\services file (db2c_db2inst1 50010/tcp)
Set the “TCP/IP Service Name” ( = db2c_db2inst1”) for the instance. Verified using “db2 get dbm cfg” command
Updated the environment variable DB2INSTANCE with the value “db2inst1”
Restarted the machine
Started the instance
ConnectionString
"Provider = IBMDADB2; Database = TIMS; Hostname = localhost; Protocol = TCPIP; Port = 50010; Uid = myUserID; Pwd = myPassword";
CODE
string queryString = "SELECT * FROM DBATABC";
try
{
using (OleDbConnection connection = new OleDbConnection(connectionString))
{
OleDbCommand command = new OleDbCommand(queryString, connection);
connection.Open();
OleDbDataReader reader = command.ExecuteReader();
if (reader.HasRows)
{
while (reader.Read())
{
if (!reader.IsDBNull(0))
{
string companyCode = reader.GetString(0).ToString();
}
}
}
reader.Close();
}
}
Note: Try to create DSN for ODBC and use ODBC connection in a sample SSIS package. This will help in resolving OLEDB connection issues also (that are common to both)

is there anyway to connect to sybase from c# without having to add a ODBC DSN connection in control panel

I am looking for a way to connect to sybase from C# without having to setup an ODBC DSN connection locally on the machine.
Is this possible? I tried all of these different connection strings:
static private DataTable Run(string sql)
{
var conn = new OdbcConnection();
const string CONN_STRING2 =
"Data Source='[myServer]';Port=5020;Database=[dbName];Uid=[user];Pwd=[pwd];";
const string CONN_STRING1 =
"Provider=Sybase.ASEOLEDBProvider.2;Server Name=[myServer];Server Port Address=5020;Initial Catalog=[dbName];User ID=[user];Password=[pwd];";
conn.Open();
var da = new OdbcDataAdapter { SelectCommand = conn.CreateCommand() };
da.SelectCommand.CommandText = sql;
var dt = new DataTable();
da.Fill(dt);
da.Dispose();
conn.Close();
return dt;
}
But I got an error stating:
{"ERROR [IM002] [Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified"}

You are using var conn = new OdbcConnection(). That is why you are getting the error.
You will need to use a sybase oledb client library. I don't know sybase at all but last I heard one needed to purchase a third-party provider. This was almost three years ago so they may have one by now.
You would then need to do something like var connection = new ASEConnection().

Download the DLL from the following link:
Sybase library
Use this library for connection:
ASEconnection connection = new AseConnection();

Use specific ADO.Net data provider stright from manufacturer (SAP now own sybase). I think you can manage to create a connection string yourself using this reference. For example:
var connStr = #"Data Source=\\myserver\myvolume\mypat\mydd.add;User ID=myUsername;
Password=myPassword;ServerType=REMOTE;"
using (ASEConnection conn = new AseConnection(connStr)) {
// use conn
}
Same informaton can be obtained from documentation mentioned earlier.