Develop Reference

Cannot add sqlite db file to Word adding deployment

I developed C# Word add-in which populates some data from database file. It is working fine while I am running through Visual studio running. But if I publish it cannot connect to database.
Here is how I get data from database:
SQLiteConnection con = new SQLiteConnection(ThisAddIn.connectionString);
con.Open();
var command = con.CreateCommand();
command.CommandText =
#"
SELECT *
FROM JK
WHERE article_number = $article_number
";
command.Parameters.AddWithValue("$article_number", textFromDoc);
using (var reader = command.ExecuteReader())
{
while (reader.Read())
{
var title = reader.GetString(2);
var article = reader.GetString(3);
ResultForm resultForm = new ResultForm();
resultForm.setArticle(title, article);
resultForm.ShowDialog();
}
}
public static string connectionString = #"Data Source=E:\projects\c#\TBPWordAddin\WordAddIn1\codexes.db";
Am I doing something wrong or do I need to include file in another way? Any help will be appreciated.
Also I tried publishing using Visual studio installer and it connected to database but the add in didnot lounched on other computers.

The connection string contains an absolute path which can be changed after publishing an application. I'd suggest using a relative path instead - in that case you will be able to find the Db easily. You may check out the following threads for more information on such kind of issues:
Connection string with relative path to the database file
How to give relative path of connection string or data source in windows form application
But if I publish it cannot connect to database.
Make sure the Db path (see the connection string) corresponds to the hardcoded value in the application used.

C# Winforms connection to MySQL AWS Database

I'm trying to connect a winforms .net application with an AWS RDS MySQL database but I am having difficulty making the connection. I have read a lot of material about connecting through Microsoft SQL database and through Elastic Beanstalk but I haven't come across the answer I'm looking for... possibly because I'm a noob.
I've looked through a few of these questions:
How to connect to MySQL Database?
https://dev.mysql.com/doc/dev/connector-net/8.0/html/T_MySql_Data_MySqlClient_MySqlConnection.htm
using MySql.Data.MySqlClient;
string connection = "server=localhost; Database=database_URL; User Id=admin;
Password=myPassword";
myConn.Open();
MessageBox.Show("Success");
I'm getting the following error message:
MySql.Data.MySqlClient.MySqlException: 'Unable to connect to any of the specified MySQL hosts.'
Is there something simple that I'm missing? I have copied the database endpoint into the database_URL location. My user id and password are correct. My database is setup on AWS as a MySQL database.

Checking back with ConnectionStrings makes it appear as if your parameter-names are wrong. 'username' should be 'uid' and 'password' should be 'pw'.
In any case I'd suggest using the MySqlConnectionStringBuilder-class to construct your connection string.
var connectionStringBuilder = new MySqlConnectionStringBuilder
{
Server = "<Instance_Ip>",
UserID = "root",
Password = "<Password>",
Database = "<Database_Name>"
};
using (var conn = new MySqlConnection(connectionStringBuilder.ToString()))

The error message is given because can't connect to the host.
In your connection string is given the localhost as the server but your database is on cloud (AWS), so it means that you must specify the database's IP or the domain name pointing to that database, not the local (local means that is in your computer). e.g.
string conn = "server=192.168.0.7; Database=database_name; User Id=admin;
Password=myPassword";
Note that the server IP is provided by AWS, and you'd make sure that ports are enable. The most common port for MySQL is 3306.
Best regards.

Try this,
//This is my connection string i have assigned the database file address path
string MyConnection2 =
"host='localhost';database='databasename';username='myusername';password='mypassword'";
//This is my insert query in which i am taking input from the user through windows forms
string Query = "Your query";
//This is MySqlConnection here i have created the object and pass my connection string.
MySqlConnection MyConn2 = new MySqlConnection(MyConnection2);
//This is command class which will handle the query and connection object.
MySqlCommand MyCommand2 = new MySqlCommand(Query, MyConn2);
MySqlDataReader MyReader2;
MyConn2.Open();
MyReader2 = MyCommand2.ExecuteReader();
// Here our query will be executed and data saved into the database.
MessageBox.Show("Save Data");
while (MyReader2.Read())
{
}
MyConn2.Close();

Using Oledb connection string for Localhost c#

When use Oledb c# connection
I noticed that a lot connection using file.
But how to connect to localhost using oledb?
I created database and tables using Microsoft SQL Server Management that connect with SQL Express and using window authentication
When using this function i don't know how should convert to connect to localhost
//Want the connString to connect localhost instead of file
public static string connString = #"Provider=Microsoft.JET.OLEDB.4.0;data source=" + Path + "\\database\\errDB.mdb";
public static OleDbConnection connection;
public myFunction()
{
string sqlString = "SELECT name,contact,accessLevel,Crudential_ID FROM errors where Crudential_ID =#ID";
connection = new OleDbConnection(connString);
OleDbCommand command = new OleDbCommand(sqlString, connection);
//Open connection
connection.Open();
command.Parameters.Add("#ID", OleDbType.VarChar);
command.Parameters["#ID"].Value = "test";
//Read from database
OleDbDataReader reader = command.ExecuteReader();
if(reader.HasRows)
{
.....
}
connection.Close();
}

connectionstrings.com - true to its name - is indispensable when you frequently need to construct connection strings. For your specific case, this would be the relevant section.
Based on that, your connection string should look something like this:
Provider=SQLNCLI11;Server=.\SQLEXPRESS;Database=SOMEDATABASE;Trusted_Connection=yes;
To break it down:
SQLNCLI11 is the SQL Native Client OLEDB provider. You can see available providers in SQL Management Studio, under Server Objects > Linked Servers > Providers.
.\SQLEXPRESS is your servername and instance. The . is shorthand for localhost (you can also use localhost if you prefer), and SQLEXPRESS is the default instance name that SQL Express installs under.
SOMEDATABASE - whatever your database name is.
Trusted_Connection=yes - Use windows authentication. Sometime you see it as Integrated Security=SSPI. They are one and the same.

If you are using SQL Express then I would suggest using a System.Data.SqlClient.SqlConnection object to make your connection. You will only need your server name to connect.
Server=ServerName\SQLEXPRESS;Database=Blah;User ID=user;Password=pw

Can't connect to database server

I'm encountering a problem with my database connection.
I started with a new blank solution, then I added a WCF library project, and last but not least a WCF website (service).
In the website i added a reference to the library where I have the interface (data contract), the class that implements the interface and the dataclasses.
what I'm trying to do is to connect to a database on a server and try to retrieve some data from there.
So the connection string looks like:
<add name="myConnectionString" connectionString="Data Source=MyServer; Initial Catalog=MyDatabase; User Id=me; Password=me123;" providerName="System.Data.SqlClient" />
and this is how I'm trying to connect with the database:
public List<string> GetEngagements(string id)
{
string sql = "SELECT myColumn FROM myTable WHERE Id = '" + id + "'";
string connString = string.Empty;
SqlConnection connDB;
connString = ConfigurationManager.ConnectionStrings["myConnectionString"].ConnectionString;
connDB = new SqlConnection(connString);
SqlCommand command = new SqlCommand(sql, connDB);
connDB.Open();
SqlDataReader rdr = command.ExecuteReader();
List<string> numbers = new List<string>();
while (rdr.Read())
{
numbers.Add(rdr[0].ToString());
}
rdr.Close();
return numbers;
}
I'm getting an exception on connDB.Open().
Then exception message says:
Failed to generate a user instance of SQL Server due to a failure in starting the process for the user instance. The connection will be closed.
I've been getting this message for 2 days now, I've googled a lot and deleted the C:\Documents and Settings\username\Local Settings\Application Data\Microsoft\Microsoft SQL Server Data\SQLEXPRESS directory but it didn't work for me..
Any solution???? help please

The error message:
Failed to generate a user instance of SQL Server due to a failure in starting the process for the user instance.
Suggests that you're using user instancing, and therefore your connection string will point to an .mdf file on disk rather than the name of a database.
So I'll assume that you want to connect to a file instance rather than a server instance.
I'll also assume that you're using SqlExpress rather than the full fat version.
In which case your connection string is wrong. It should look more like this:
"Data Source=.\SQLEXPRESS;
AttachDbFilename=fileOnDisk.mdf;
Integrated Security=True;
User Instance=True;"
User instancing means that this server instance and the DB inside will only be visible to the application opening the connection string.
You don't have to use user instancing - you can set User Instance=False or just leave it out. Then once the application has made the connection you can connect other tools to the server instance and connect to the DB yourself.

How to connect to the Remote Database using Connection String in C#.net

every one. I want to connect a remote database using Sql Connection String in C#.net, I am trying it to do, but failed to connect. I am new to C#.net connections to the Database. Can any one pls tell me how to write the Connection String.

Check this website for the specific format: http://www.connectionstrings.com/

Here is a little bit of code that will connect to a dabase called myDatabase on a server called myServer, query the myTable table for the column myColumn, and insert the returned data into a list of strings.
While by no means exaustive or perfect, this snippet does show some of the core aspects of working with data in C#.
List<string> results = new List<string>();
SqlConnection conn = new SqlConnection("Data Source = myServerAddress; Initial Catalog = myDataBase; User Id = myUsername; Password = myPassword;");
using (SqlCommand command = new SqlCommand())
{
command.Connection = conn;
command.CommandType = CommandType.Text;
command.CommandText = "Select myColumn from myTable";
using (SqlDataReader dr = command.ExecuteReader())
{
while (dr.Read())
{
results.Add(dr["myColumn"].ToString());
}
}
}

There is no difference in this regard. The connection string to connect to remote server database is written same as you write to connect to local database server.
However, only Data Source changes.
Below is a sample connection string
User ID=dbUserName;Password=dbUserPwd;Initial Catalog=dbName;Data Source=remoteMachine\serverInstanceNameIfAny;
But by default sql server is not configured to Sql Server Authentication, so you need to enable
Sql server authentication
Also Create a Log in user in the database

Here are a couple of examples:
With Integrated Security
Server=RemoteMachineName\Intance; Initial Catalog=DatabaseName; Integrated Security=true;
With username and password
Server=RemoteMachineName\Intance; Initial Catalog=DatabaseName; UID=Username; PWD=Password;

You can also do that in web.config file
<configuration>
<ConnectionStrings>
<add name="YourConnectionString" connectionString="Data Source=Nameofserver;
InitialCatalog=NameofDatabase;Persist Security Info=True;
UserID=DatabaseUserID;Password=DatabasePassword" providerName="System.Data.SqlClient"/>
</connectionStrings>
</configuration>