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EF Core DbContext connection management for native queries

I'm using EF core 6 with NpgSql (connection pooling enabled) and I need to execute a native query for a specific use case. I'm trying to figure out the best way to manage the database connection for native queries inside an ASP.Net Core app. The query is executed inside a scoped service. I am doing the following and it's "working":
_dbContext.Database.OpenConnectionAsync(cancellationToken);
var npgsqlConnection = _dbContext.Database.GetDbConnection() as NpgsqlConnection;
await using var cmd = new NpgsqlCommand(Sql, npgsqlConnection);
// execute cmd, connection isn't closed by me
There are a couple of questions like this already but I wasn't satisfied with the answers. For example some say "if you open the connection you should close it". But this breaks the next time I use the DbContext.
It works if I don't close the connection and it doesn't exhaust the connection pool even if I execute it many times. I assume there is some magic going on and it's released back to the pool when the scope is disposed?
Other way would be to create & close the NpgsqlConnection directly. Is there a better way?

Azure function using entity framework but connect string not working

I have a azure V1 function using a project dll that handles entity framework.
First I set connect string like
metadata=res://*/Dev.csdl|res://*/Dev.ssdl|res://*/Dev.msl;
provider=System.Data.SqlClient;
provider connection string='
data source={IP};initial catalog={DBName};
persist security info=True;
user id={User};password={PW};
MultipleActiveResultSets=True;
App=EntityFramework'
and I got
Keyword not supported: 'metadata'.
then I changed my connect string to
data source={IP};initial catalog={DBName};persist security info=True;user id={User};password={PW};
and I got
The context is being used in Code First mode with code that was generated from an EDMX file for either Database First or Model First development. This will not work correctly. To fix this problem do not remove the line of code that throws this exception. If you wish to use Database First or Model First, then make sure that the Entity Framework connection string is included in the app.config or web.config of the start-up project. If you are creating your own DbConnection, then make sure that it is an EntityConnection and not some other type of DbConnection, and that you pass it to one of the base DbContext constructors that take a DbConnection. To learn more about Code First, Database First, and Model First see the Entity Framework documentation here: http://go.microsoft.com/fwlink/?LinkId=394715
And here's my code
DevEntities db = new DevEntities();
var lstAcAccount = db.AcAccounts.ToList();
return req.CreateResponse(HttpStatusCode.OK, lstAcAccount);
DevEntities is from other dll project that using the connect string above.
So, what should I do to make this work?

You shouldn't use generated connection string, now you have all metadata files included in your solution. Instead try use in connection string section of app.config:
"data source=localhost\sqlexpress; initial catalog=sample; integrated security=True;MultipleActiveResultSets=True;"
If it is Database first:
Open the .edmx[Diagram] -> right click -> "Update Model from database"
And see if the will appear the "Add", "Refresh" and "Delete" tabs.
If doesn't... probably your connection is broken and the dialog for VS creates a new connection string will appear instead.
Hope it helps.

C# & SQL Server : how to set quote_identifier off in ole db connection string

I've inherited an Access DB and migrated the data to a SQL Server DB. I would like to know if there's a similar parameter to QuoteId (ODBC) for OLE DB (I'm forced to use OLE DB here) for the connection string. This would allow me to set it only once in the config and have it done with.
Is there a way to achieve this?
Please let me know if you need further information, but I think the key issue is just to know if there's an equivalent to OCDB-QuoteId for the OLE DB connection string (MS doesn't state any in their help pages).
Thanks a bunch

Entity framework connecting to database with app.config

I'm developing a program using entity framework with WPF and using a SQL credentials on the database.
When deploying the program it produces the program.exe.config file which contains the connection string. Any user can open it and see the credentials data (SQL username & password). I searched to figure out a way to hide them or encrypt but nothing useful in my case. I found that entity using base variable to get the connection from the app.config but when I tried after many ways to pass the connection string directly an the right way I faced a problem about the provider in the connection string.

[Solved]
i let the connection with app.config but with fake data for username and password .
then i created a setting to store the connection string . and at the instantiating of the db entity i changing the connection property stored in the settings . so i guess that your connection is safe now .

Find connection string for connecting to MySQL Server 5.1.50 using OleDbConnection

I am interested how can I find the connection string in order to be able to connect to MySQL Server 5.1.50 using OleDbConnection(C#).
I used this auto generated string (after adding new data source in Visual Studio):
server=localhost;User Id=MyID;password=MyPassword;database=MyDatabase
but I always get the same error message:
An OLE DB Provider was not specified in the ConnectionString. An example would be, 'Provider=SQLOLEDB;'.
I have tried different providers but neither of them seems to work.

Is there a reason you aren't using the MySQL .NET connector? Anyways, I think you need to add
Provider=MySQL Provider; to your connection string.
try this as your connection string:
Provider=MySQL Provider;server=localhost;User Id=MyID;password=MyPassword;database=MyDatabase;
The MySQL.NET connector fully implements the ADO.NET interface. Every command is identical to using the System.Data.SqlClient namespace.