I make a small project in Unity and I'm having a problem when I want to use the System.Data(.SqlClient) package. I tried to make a 'custom' reference, to the dll I downloaded separately for this purpose and got no luck with it. Anybody faced this problem before? I just can't get it to work. I want to use an SQL server with the game I'm doing but can't use commands like SqlConnection. The weird thing is that I succeded in Visual Studio (doesn't appear in the error list) but when I return to Unity it's still shown as a compiler error.

Edit: Just to clarify. I tried to use the default dll. I used NuGet to get another one. I used PowerShell's install command to get the System.Data.dll and also download 2 different from the internet from a trustworthy site. None of these ones are working with my Unity project.

Thank you for your help in advance!

CodePudding user response：

The solution that helped me is to set the Framework Unity uses from .NET Standard 2.1 to .NET Framework.

Exact steps: EDIT -> Project Settings -> Player -> Api Compatibility Level -> Set from .NET Standard 2.1 to .NET Framework || After that it worked for me.