I want to create a simple tool that connect to SQL Server then list all databases, and after user selects one of those databases, the tool will perform some SQL scripts on it.
Below is a method that should return a DataTable contains all my databases;
I send to it sqlServerIp as first parameter like 10.10.20.30 ip address not server name.
Also I didn't specify a SQL Server instance.
private DataTable GetSqlServerDatabases(String sqlServer, bool isWindowsAuth, String login, String password)
{
String connectionString;
DataTable databases;
if (isWindowsAuth)
{
connectionString = "Data Source=" + sqlServer + ",1433;Network Library=DBMSSOCN; Integrated Security=True;";
}
else
{
connectionString = "Data Source=" + sqlServer + ",1433;Network Library=DBMSSOCN;" + "User id=" + login + ";Password=" + password + ";";
}
try
{
using (var con = new SqlConnection(connectionString))
{
con.Open();
databases = con.GetSchema("Databases");
foreach (DataRow database in databases.Rows)
{
String databaseName = database.Field<String>("database_name");
short dbID = database.Field<short>("dbid");
DateTime creationDate = database.Field<DateTime>("create_date");
}
}
}
catch(Exception ex)
{
databases = null;
MessageBox.Show(ex.Message.ToString());
}
return databases;
}
When I try to call the method on more than one server I faced an exception:
Login failed. The login is from an untrusted domain and cannot be used with Windows authentication.
or
A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible.
I used connection string with Network Library=DBMSSOCN; after searching here on SO and web so I don't know what is the wrong with this method.
Remove Integrated Security parameter. This parameter is for trusted connections.
More samples on http://www.connectionstrings.com/sql-server
Related
I'm trying to connect to my local SQL express database with following code with no luck :
string strConnectionString = null;
SqlConnection cnn = null;
strConnectionString = "Data Source=" + txtSQLServer.Text.Trim() + ";Initial Catalog=" + txtSQLDatabase.Text.Trim() + ";User ID=user;Password=user";
cnn = new SqlConnection(strConnectionString);
MessageBox.Show(strConnectionString);
try
{
cnn.Open();
MessageBox.Show("Connection Open ! ");
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
The sql express database is running, because I can connect with it through SQL server management studio.
I already tried "localhost", "127.0.0.1", "PC-name/SQLEXPRESS"
error says : 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.
What more can I try?
edit : ok, found the problem
I needed to start the SQL server browser
connect to "PC-name/SQLEXPRESS"
But in the future I want to connect to an IP-address, how do I do this?
I tried this connection string :
strConnectionString = "Data Source=" + txtSQLServer.Text.Trim() + ",1433;Network Library=DBMSSOCN; Initial Catalog=" + txtSQLDatabase.Text.Trim() + ";User ID=user;Password=user";
I wanted to insert some data to the mysql database using that ID that I have retrieved from datagridview. i am new in programming. can someone please help me? thanks
First you need to download and intall
MySQL ADO.Net connector
it's the official ado.net connector for C# applications. once you intall that you can use ado.net standered data access methods to save data.
basic steps
First create a connection to the my sql data base.
Then create a command object contains the insert command.
then provide the object that contain the so called ID and finalize the command object
then Execute the command against the database.
Sample code
This is the class variables that will be used later
private MySqlConnection connection; // this MySqlConnection class comes with the connector
private string server;
private string database;
private string uid;
private string password;
This will Initialize method will configure the connection with the configuration data
private void Initialize()
{
server = "localhost";
database = "connectcsharptomysql";
uid = "username";
password = "password";
string connectionString;
connectionString = "SERVER=" + server + ";" + "DATABASE=" +
database + ";" + "UID=" + uid + ";" + "PASSWORD=" + password + ";";
connection = new MySqlConnection(connectionString);
}
this method will open a connection to the database . you should write a C Lose method as well .because it's best practice to always close the connection after you used it
private bool OpenConnection()
{
try
{
connection.Open();
return true;
}
catch (MySqlException ex)
{
//When handling errors, you can your application's response based
//on the error number.
//The two most common error numbers when connecting are as follows:
//0: Cannot connect to server.
//1045: Invalid user name and/or password.
switch (ex.Number)
{
case 0:
MessageBox.Show("Cannot connect to server. Contact administrator");
break;
case 1045:
MessageBox.Show("Invalid username/password, please try again");
break;
}
return false;
}
}
This will insert a record to database . query will contains the T-SQL query that runs against the database
public void Insert()
{
string query = "INSERT INTO tableinfo (name, age) VALUES('John Smith', '33')";
//open connection
if (this.OpenConnection() == true)
{
//create command and assign the query and connection from the constructor
MySqlCommand cmd = new MySqlCommand(query, connection);
//Execute command
cmd.ExecuteNonQuery();
//close connection
this.CloseConnection();
}
}
Hope this will help
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.
I have a WPF application that accesses a SQL server using SqlConnection with a connection string.
private string connString =
"user id=*****;" +
"password=*****;" +
"server=1.1.1.1;" +
"Trusted_Connection = yes;" +
"database=****;" +
"connection timeout = 30";
private SqlConnection myConnection = new SqlConnection(connString);
The string contains the username and password for the account I want the program to use to access the database. This works as I would expect it to on my machine. Once I run it on another machine I get a an error:
"Login failed for user 'Domain\local user'"
I am sure that I am just missing some sort of setting or configuration.
Any help would be great
Trusted_Connection = yes tells SQL Server to use Integrated (Windows) Authentication. Your user name and password are ignored.
I'm connecting to a mysql database in c#, and it all works well as long as I input the server address as "localhost" or its ip, but if I try a remote ip it fails with:
Error: 0 : Unable to connect to any of the specified MySQL hosts.
here's the code:
server = Properties.Settings.Default.DBHost;
port = Properties.Settings.Default.DBPort;
database = Properties.Settings.Default.DBName ;
uid = Properties.Settings.Default.DBUser;
password = Properties.Settings.Default.DBPassword ;
string connectionString;
connectionString = "SERVER=" + server + ";" + "PORT=" + port + ";" + "DATABASE=" + database + ";" + "UID=" + uid + ";" + "PASSWORD=" + password + ";";
connection = new MySqlConnection(connectionString);
[...]
if (this.OpenConnection() == true){
// exec db operations
}
else{
MessageBox.Show("Database Connection Error.");
}
Tested:
No firewall restrictions
Same error in different computers
Already tried on with different remote databases, all with set privileges and accessible from other sources
If its your mysql server then,
Check you port is open or not. (probably 3306)
Change your bind-address in your my.ini file (from 127.0.0.1 to 0.0.0.0)
Double check the user your trying to connect to server has necessary privileges
If its not your mysql server then,
Ask the provider whether they are supporting remote connections or not.
1st you have to check if your server is supporting remote MySQL database Connection then
You can try this MySQL Connection String Builder example, i'm working with all the time .. no errors :
_connectionStr = new MySqlConnectionStringBuilder
{
Server = "127.0.0.1",
Database = myDatabase,
UserID = myUserName,
Password = myPassword,
ConnectionTimeout=60,
Port = 3306,
AllowZeroDateTime = true
};
_con = new MySqlConnection(_connectionStr.ConnectionString);
try
{
_con.Open();
}
catch
{
MessageBox.Show("Error, help i can't get connected!");
}
Hope this works!
Maybe your MySQL Server is not configured to listen to any of your IP Interface.
Maybe it is just listening into your "localhost:3306"
Check it in your MySQL Server config file "bind-address".