I have a database the have orders, and which order many order items, that kinds of thing. I deleted one product carelessly, and it is related to the order items, so it can't load successfully. So, I use the SQLite Database Browser to delete the orders and order items. But after I restart the server, it prompt me that :
We're sorry, but something went wrong. We've been notified about this issue and we'll take a look at it shortly.
Notice that I am using the development mode.