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Cannot set Connection String to LocalDb using OLEDB

Good morning guys,
I feel quite silly to ask this question, but I have looked everywhere and possibly at all questions in this matter and could not find a solution that would work for me.
Long story short.
I am using a local database called TestDB.mdf in windows form application. The application is designed to do (as per current) two simple things.
1. Import data from excel document into the database - which I don't have any issues with.
and...
2. Clear all data stored in that database - this is where I am struggling
For the import data into the database (point 1) I am using two connection strings. One for excelConnectionString
string excelConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source= " +
"C:\\Users\\User.AR\\Desktop\\export.xls; " +
"Extended Properties=\"Excel 8.0;HDR=YES;IMEX=1;\"";
and second for sqlConnectionString
string sqlConnectionString = #"Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=c:\users\arkadiusz.rzepka\source\repos\Database_application\Database_application\TestDB.mdf;Integrated Security=True";
Then I use SqlBulkCopy to import all data and all is working like a charm.
Now the issue I can see is that I cannot open a connection to clear all data from the same database.
I have navigated to properties of my database to find connection string and this has been presented in the below format:
Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=C:\Users\User.AR\source\repos\Database_application\Database_application\TestDB.mdf;Integrated Security=True
I have had to amend the above connection string as I was getting errors such as missing provider, should be like Provider=SQLOLEDB, after adding a provider, I have had to change Integrated Security = SSPI, and now I am getting error such as SQL Server does not exist or access denied
My code just to check if the connection was opened is presented below and I would be grateful if you could advise of what I am doing wrong.
private void DeleteAllRecords()
{
string connectionString = #"Provider=Sqloledb;Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=C:\Users\User.AR\source\repos\Database_application\Database_application\TestDB.mdf;Integrated Security=SSPI";
using (OleDbConnection connection = new OleDbConnection(connectionString))
{
try
{
connection.Open();
MessageBox.Show("Connection openned successfully!");
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
}

If you run this in the command prompt.
SqlLocalDB.exe i "MSSQLLocalDB"
You will get the instance pipe name. You should be able to use that in your OLEDB connection. This has worked for me when connecting Excel using OLEDB connection to my MSSQLLocalDB.
Name: MSSQLLocalDB
Version: 13.1.4001.0
Shared name:
Owner: Foo\Foo.Bar
Auto-create: Yes
State: Running
Last start time: 18/03/2021 09:00:34
Instance pipe name: np:\\.\pipe\LOCALDB#DA1FAFF6\tsql\query
So my final connection string in excel looked like this.
provider=SQLOLEDB;initial catalog=IpsosDC;data source=np:\\.\pipe\LOCALDB#DA1FAFF6\tsql\query

Try using double bar on the paths of your connection strings, instead of one. So it would be like this:
string connectionString = #"Provider=Sqloledb;Data Source=(LocalDB)\\MSSQLLocalDB;AttachDbFilename=C:\\Users\\User.AR\\source\\repos\\Database_application\\Database_application\\TestDB.mdf;Integrated Security=SSPI";

Connect to online MySQL database in C# desktop application

I have a problem with connecting to the database.
private static readonly string s_connectionString = "Server=db.inu.hu; Database=patientRegistry;UID=****; Password=****; Port=3306; Trusted_Connection=true";
That's my connection string and with this I can't open the connection.
using (SQLiteConnection conn = new SQLiteConnection(s_connectionString))
{
conn.Open();
}
I thought the problem might be that I have a table in the database and need to add that to the connection string.

Are you trying to connect to MySQL or SQLite? You are referencing a SQLiteConnection object, but I think you need to be using a MySqlConnection connection object instead.

connecting Access DB to VS using C#

This is the 1st time I am using C# connection with db, also I dont use access.
I just want to know the initial steps required to connect the access db to visual studio C# windows application.
I have searched though the internet, It helped a lot. I cant find my mistake in the code. I think I am missing some steps in establishing the connection with the db.
here is the error that appears when I try to run the program "'\f38910\Users\kainat.baig\Desktop\AAA\Database101' is not a valid path. Make sure that the path name is spelled correctly and that you are connected to the server on which the file resides."
CODE:
OleDbConnection bookConn;
OleDbCommand oleDbCmd = new OleDbCommand();
String connParam = #"Provider=Microsoft.Jet.OLEDB.4.0;Data Source= \\f38910\Users\kainat.baig\Desktop\AAA\Database101; Persist Security Info=False";
public Form1()
{
bookConn = new OleDbConnection(connParam);
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
bookConn.Open(); //*ERROR LINE
oleDbCmd.Connection = bookConn;
bookConn.Close();
}

First your file name does not have the file extension name like .mdb
Database101\MyDB.mdb
Second, if it is in a network. Would it be better if you net use first in you DOS prompt to assign a drive letter for your network, like:
net use z: \\f38910\Users\kainat.baig\Desktop\AAA\Database101 your_password /USER:your_account
Then your connection string will be shorter then:
String connParam = #"Provider=Microsoft.Jet.OLEDB.4.0;Data Source= z:\MyDB.mdb; Persist Security Info=False";
If the file extension by the way is .accdb instead of .mdb it should be:
String connParam = #"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=z:\MyDB.mdb;;Persist Security Info=False;"
Or simply your path is simply wrong.
Go to windows explorer and just clink on the path where your file is and copy paste it.

You forget to add .mdb after database name or .accdb if you are using Microsoft Office Access 2007 or higher database but, for that you have to change Provider also.
String connParam = #"Provider=Microsoft.Jet.OLEDB.4.0;Data Source= \\f38910\Users\kainat.baig\Desktop\AAA\Database101.mdb; Persist Security Info=False";
Or you can use connection string like this
String connParam = #"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=\\f38910\Users\kainat.baig\Desktop\AAA\Database101.mdb;User Id=admin;Password=;"
EDITED:
for ACCESS 2010
#"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=\\f38910\Users\kainat.baig\Desktop\AAA\Database101.accdb"

C# enctypted .accdb connection

I recently updated my database from .mdb (MS Access 2003) to .accdb (MS Access 2010).
With this update I also updated my provider from: Microsoft.Jet.OLEDB.4.0 to Microsoft.ACE.OLEDB.12.0
The connection works ok when I use a .accdb file without a password, but once I choose to
Encrypt with Password
I receive the following error when I try to open a connection.
Cannot open database ''. It may not be a database that your
application recognizes, or the file may be corrupt.
Used connection string:
Provider=Microsoft.ACE.OLEDB.12.0;Data Source=D:\\App\\Main\\bin\\Debug\\db.xxx;
Jet OLEDB:Database Password=MyPass;
Note: I use a custom extension for my .accdb file, this was used for .mdb files without problems and I assume this should not be a problem (tested).

I don't see a problem with your connection string. Still I would try it from VBA to see whether that effort sheds any light on the problem.
This one worked from Access 2007 whether I named the db file with "accdb" or "xxx" file extension. The single quotes are not required around my password; the code succeeded whether or not I included the single quotes.
Public Sub OleDbToEncryptedAccdb()
'Const cstrDb As String = "encryptd.accdb" '
Const cstrDb As String = "encryptd.xxx"
Const cstrFolder As String = "C:\share\Access"
Const cstrPassWord As String = "letmein"
Dim cn As Object
Dim strConnect As String
strConnect = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" & _
cstrFolder & Chr(92) & cstrDb & _
";Jet OLEDB:Database Password='" & cstrPassWord & "';"
Debug.Print strConnect
Set cn = CreateObject("ADODB.Connection")
cn.ConnectionString = strConnect
cn.Open
cn.Close
Set cn = Nothing
End Sub
Edit: Apparently Access 2010 provides a stronger encryption method than earlier Access versions. With db.xxx open in Access 2010, check which ACE version is used as the Provider.
? CurrentProject.Connection.Provider
If it replies something like Microsoft.ACE.OLEDB.14.0, use that in your c# connection string.

Creating an SQL Server connection string without importing a datasource in C#

I am going off of this tutorial: http://www.dotnetperls.com/sqlclient . Instead of adding a data source and a having visual studio compile my connecting string - I want to do it myself. The reason being is that the database will not always be the same and I want this application to be able to use different databases depending on which I point it to.
So how can I manually create the connection string? I am using SQL Server 2005.

Step 1: Go to connectionstrings.com and find the proper format for your database.
Step 2: Plug in the appropriate values to the connection string.
Step 3: Pass that string to the constructor of SqlConnection.
I would also suggest storing your connection string in your app.config/web.config file. You can then modify them easily if needed. The proper format can be found at MSDN - connectionStrings element. You then change your code to:
SqlConnection sqlConn = new SqlConnection(
ConfigurationManager.ConnectionStrings["ConnStringName"].ConnectionString);

I don't see where the connection string is "compiled".
In the code
SqlConnection con = new SqlConnection(
ConsoleApplication1.Properties.Settings.Default.masterConnectionString)
ConsoleApplication1.Properties.Settings.Default.masterConnectionString is a field and it can be replaced with any other appropriate string.

for SQL Server format of the connection string is
"Data Source = server_address; Initial Catalog = database_name; User ID = UserId; Password = **;"
save this connection string in a string variable and use with connection object.
either way you can add in web.config file.
<ConnectionString>
<add name = "name_of_connecctionString" ConnectionString = "Data Source = server_address; Initial Catalog = database_name; User ID = UserId; Password = ****;" ProviderName = "system.Data.SqlClient"/>
</ConnectionString>
you can change the provider as needed by you.
then in code behind file access this particular connection string using configuration manager.