C# - Can't connect to remote MySQL server - c#

My problem is that I can't connect to my website remote MySQL server. I have read all answers in stackoverflow.com, but I can't find right answer. Here's my C# code:
using System;
using System.Collections.Generic;
using System.Data;
using System.Data.SqlClient;
namespace ConsoleApplication3
{
class Program
{
static void Main(string[] args)
{
SqlConnection con;
string connectionString = #"Server=[IP adress];Port=3306;Database=[database];Uid=[user];Pwd=[pass];";
con = new SqlConnection(connectionString);
try
{
con.Open();
Console.WriteLine ("Connection Open ! ");
}
catch (Exception ex)
{
Console.WriteLine("Can not open connection ! ");
Console.WriteLine(ex.Message); //shows what error actually occurs
}
Console.ReadLine();
}
}
}
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)
Any ideas?

When connecting to a MySQL-Database I always used the MySQL Connector you can get here: https://dev.mysql.com/downloads/connector/net/6.9.html
You have to import the MySQL namespaces to your project and then you can use the MySQLConnection instead of the SQLConnection that is, as far as I know, only for MSSQL servers.
http://www.codeproject.com/Tips/423233/How-to-Connect-to-MySQL-Using-Csharp

try the following
string connectionString = #"Server=[IP adress]:3306;Database=[database];Uid=[user];Pwd=[pass];";
instead of
string connectionString = #"Server=[IP adress];Port=3306;Database=[database];Uid=[user];Pwd=[pass];";

Related

Cannot connect to MySQL database in C#.NET

So I'm following this tutorial: http://support.microsoft.com/kb/314145/
and I get an unexpected error: A first chance exception of type 'System.Data.SqlClient.SqlException' occurred in System.Data.dll
My class looks like this:
class Database
{
public Database()
{
string connectionString = "Password=pass;User ID=userid;Initial Catalog=soksko;Data Source=(local)";
using (SqlConnection connection = new SqlConnection(connectionString))
{
connection.Open();
Console.WriteLine("ServerVersion: {0}", connection.ServerVersion);
Console.WriteLine("State: {0}", connection.State);
}
Console.WriteLine("Database: OK");
}
}
I googled, but I couldnt find anything valuable. I am using MySQL database, it is on the same computer and I am using VS 2013. I successfully added my database to Server Explorer with the same connection information that I use above, but I get exception, when I try to open the connection.
See this link for how a MySQL connection string should look:
ASP.NET use SqlConnection Connect Mysql
See this link for an explanation of the oft mis-used Data Source=(local):
http://blogs.msdn.com/b/sql_protocols/archive/2008/09/19/understanding-data-source-local-in-sql-server-connection-strings.aspx
hint you're not using SQL-Server so it won't work for you
SqlConnection is for MS SQL Server. For MySql you need to use a MySqlConnection class provided by the MySQL connector (http://dev.mysql.com/doc/connector-net/en/index.html)
using MySql.Data.MySqlClient;
using(MySqlConnection myConnection = new MySqlConnection(myConnectionString))
{
myConnection.Open();
// execute queries, etc
}
The tutorial you're using is for Sql Server, not MySQL.

Error 1042 MySql C#?

I can't connect to my MySql database via my C# cmd it gets me error 1042
this code is from:
http://social.msdn.microsoft.com/Forums/vstudio/en-US/67226fe6-175a-4f8b-96ab-a22fd836617f/inserting-values-to-mysql-using-c
using System;
using System.Diagnostics;
using System.Windows.Forms;
using System.Runtime.InteropServices;
using MySql.Data.MySqlClient;
class MyClass
{
public static void Main()
{
MySqlConnection conn = new MySql.Data.MySqlClient.MySqlConnection();
MySqlCommand cmd = new MySql.Data.MySqlClient.MySqlCommand();
string SQL;
conn.ConnectionString = "server=SERVER; userid=USER;password=PASSWORD;database=DATABASE;";
try
{
conn.Open();
MessageBox.Show("Files Inserted into database successfully!",
"Success!", MessageBoxButtons.OK, MessageBoxIcon.Asterisk);
conn.Close();
}
catch (MySql.Data.MySqlClient.MySqlException ex)
{
MessageBox.Show("Error " + ex.Number + " has occurred: " + ex.Message,
"Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
}
UPDATE - SOLVED
SOLVED the server name was a bad url
i used
db4free.net
maybe the dash in my host was the problem
MySQL error 1042 (HY000) is reported from the MySQL server when it can't resolve the client IP address into a hostname.
On our MySQL servers, we disable hostname resolution, and use IP addresses instead.
If you don't want to disable hostname resolution, then you need to ensure that MySQL can resolve your client IP address into a hostname, either by adding an appropriate entry to the /etc/hosts file (on the MySQL server host), or adding an appropriate entry to the DNS server(s).
Otherwise, you can disable hostname resolution by adding skip-name-resolve in the [mysqld] section of the MySQL server configuration file (and restarting the MySQL server). NOTE: Any current users defined using a hostname won't be able available, since MySQL will now be looking (defined in the mysql.users table) for users of the form "foo#192.168.1.33", rather than "foo#tyrion", and MySQL isn't going to find a match. (This isn't a problem if your users are all defined with the % wildcard as the hostname.)
I was facing same issue,i was tring to connect to remnote mysql server using my window 7 os machine but in my case disabling firewall solved my problem

Connect to SQL Server 2012 Database with C# (Visual Studio 2012)

Evening all,
I'm trying to connect to a SQL Server 2012 database from C#. My connection settings when using SQL Server Management Studio are as below:-
Server Type: Database Engine
Server Name: Paul-PC\SQLEXPRESS
Authentication: Windows Authentication
Username: Greyed out
Password: Greyed out
The name of the database I'm trying to connect to is "testDB".
Here's my code:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Data.SqlClient;
namespace DatabaseConnection
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void btnConnect_Click(object sender, EventArgs e)
{
SqlConnection myConnection = new SqlConnection("server=localhost;" +
"Trusted_Connection=yes;" +
"database=testDB; " +
"connection timeout=30");
try
{
myConnection.Open();
MessageBox.Show("Well done!");
}
catch(SqlException ex)
{
MessageBox.Show("You failed!" + ex.Message);
}
}
}
}
Unfortunately, my code fails to connect with the following error:-
"You failed!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."
Any suggestions? SQL Server is running locally.
In your connection string replace server=localhost with "server = Paul-PC\\SQLEXPRESS;"
I tested all the answers here, but for me, none worked. So I studied a bit the problem, and finally I found the connection string needed. To get this string, you do:
1. in you project name:
a. right click the project name,
b. click Add,
c. select SQL Server Database (obviously you can rename it as you wish).
Now the new desired database will be added to your project.
2. The database is visible in the Server Explorer window.
3. Left click the database name in the Server Explorer window; now check the Solution Explorer window, and you will find the "Connection String", along side with Provider, State, Type, Version.
4. Copy the connection string provided, and put it in the Page_Load method:
string source = #"Data Source=(LocalDB)\v11.0;AttachDbFilename=c:\x\x\documents\visual studio 2013\Projects\WebApplication3\WebApplication3\App_Data\Product.mdf;Integrated Security=True";
SqlConnection conn = new SqlConnection(source);
conn.Open();
//your code here;
conn.Close();
I renamed my database as Product. Also, in the "AttachDbFilename", you must replace "c:\x\x\documents\" with your path to the phisical address of the .mdf file.
It worked for me, but I must mention this method works for VS2012 and VS2013. Don't know about other versions.
Try:
SqlConnection myConnection = new SqlConnection("Database=testDB;Server=Paul-PC\\SQLEXPRESS;Integrated Security=True;connect timeout = 30");
Replacing server=localhost with server=.\SQLEXPRESS might do the job.
Note to under
connetionString =#"server=XXX;Trusted_Connection=yes;database=yourDB;";
Note: XXX = . OR .\SQLEXPRESS OR .\MSSQLSERVER OR (local)\SQLEXPRESS OR (localdb)\v11.0 &...
you can replace 'server' with 'Data Source'
too you can replace 'database' with 'Initial Catalog'
Sample:
connetionString =#"server=.\SQLEXPRESS;Trusted_Connection=yes;Initial Catalog=books;";
use this style
#"server=.\sqlexpress;"

Connecting C# to SQL Server Compact database

Hi I'm trying to connect an SQL server compact database to my program and I want a button that deletes all entries from the database, when I Press said button the program throws an exception and gives the following 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: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified)"
Help Please? =]
Sorry, Code is Below =]
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.SqlClient;
using System.Data.SqlServerCe;
namespace Booking_system_Final
{
public partial class PendingJobs : Form
{
SqlConnection sc = new SqlConnection("Data Source=C:\\Users\\Administrator\\My Documents\\BMS_Data.sdf");
public PendingJobs()
{
InitializeComponent();
}
private void PendingJobs_Load(object sender, EventArgs e)
{
// TODO: This line of code loads data into the 'bMSDataSet.Bookings' table. You can move, or remove it, as needed.
this.bookingsTableAdapter.Fill(this.bMSDataSet.Bookings);
// TODO: This line of code loads data into the 'bMS_DataDataSet1.Bookings' table. You can move, or remove it, as needed.
}
private void button1_Click(object sender, EventArgs e)
{
sc.Open();
SqlCommand cmd = new SqlCommand("DELETE FROM Bookings");
cmd.Connection = sc;
cmd.ExecuteNonQuery();
sc.Close();
MessageBox.Show("Database Cleared");
}
}
}
Try use SqlCeConnection class rather than SqlConnection:
SqlCeConnection sqlConnection1 = new SqlCeConnection();
sqlConnection1.ConnectionString = "Data Source = C:\\Users\\Administrator\\My Documents\\BMS_Data.sdf;Persist Security Info=False";
If you want to connect to SQL Server Compact, use SqlCeConnection, SqlCeCommand etc. Add a reference to the SQL Server Compact ADO.NET provider, System.Data.SqlServerCe.dll
Have a look at this blog article: SQL SERVER – FIX : ERROR : (provider: Named Pipes Provider, error: 40 – Could not open a connection to SQL Server)
This goes step-by-step through what you might need to do:
In short:
SQL Server should be up and running.
Enable TCP/IP in SQL Server Configuration
Open Port in Windows Firewall
Enable Remote Connection
Enable SQL Server Browser Service
Create exception of sqlbrowser.exe in Firewall
Recreate Alias
About the where and what to do in each step, you will find more in-depth information in the article.
You may also want to have a look at the Connection strings for SQL Server Compact. There you can find other variations of the connection string you could try to play with.
You seems to be using a bad connection string. (Or the file path is wrong). Check out http://www.connectionstrings.com/sql-server-ce for connection string options.

Exception when trying to connect to .sdf database

I have database in file C:\Users\Pawel\Documents\DB.sdf. How can I connect to it?
Simple code below does not work and generates exception.
Code:
[WebMethod]
public String TestCon()
{
SqlConnection sql = new System.Data.SqlClient.SqlConnection(
#"Data Source=C:\Users\Pawel\Documents\DB.sdf");
string str = "OK";
try
{
sql.Open();
sql.Close();
}
catch (Exception ex)
{
str = ex.Message;
}
return str;
}
Result:
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 am I missing? What I should do to open connection correctly?
EDIT:
System.NotSupportedException: SQL Server Compact is not intended for ASP.NET development.
Great :P
Consider using System.Data.SqlServerCe.SqlCeConnection:
System.Data.SqlServerCe.SqlCeConnection con =
new System.Data.SqlServerCe.SqlCeConnection(#"Data Source=C:\Users\Pawel\Documents\DB.sdf");
(Add a reference to System.Data.SqlServerCe, if necessary)
Also, to use it with ASP.NET, add:
AppDomain.CurrentDomain.SetData("SQLServerCompactEditionUnderWebHosting", true);
Apparently, you are using a SQL Compact Edition (sdf file). Have you tried using SqlCeConnection instead of SqlConnection ?
As a bonus: if you dont want to mess with connectionstrings anymore, please try this.
Do do so, you have to add a reference to System.Data.SqlServerCe assembly.

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