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PomeloFoundation / Pomelo.EntityFrameworkCore.MySql

Entity Framework Core provider for MySQL and MariaDB built on top of MySqlConnector
MIT License
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Unable to cast object of type 'System.DBNull' to type 'System.String' #1725

Open J031PC opened 1 year ago

J031PC commented 1 year ago

Steps to reproduce

Sorry, I don't understand any English..

Upgrade a project from .net6 to .net7, when executing this query it gives me an error.

var vm = await _context.Users
    .Where(e => e.Id == request.Id)
    //.ProjectTo<GetUserDetailVm>(_mapper.ConfigurationProvider)
    SingleOrDefaultAsync(cancellationToken);

The issue

I think it is related to MySqlConnector:

System.InvalidCastException: Unable to cast object of type 'System.DBNull' to type 'System.String'.

Further technical details

MySQL version: 5.7.33 Operating system: Mac M1 Pomelo.EntityFrameworkCore.MySql version: 7.0.0-alpha.1

Other details about my project setup: The project use Mediatr (commands/queries) for ddd and clear architecture.

mguinness commented 1 year ago

Your English is good. Please use code blocks instead of posting screenshots. See https://github.com/PomeloFoundation/Pomelo.EntityFrameworkCore.MySql/issues/1571 regarding your issue.