I have a huge doubt about this, as I mentioned in my previous question I am working on a C# and DevExpress end of class project.
This is the error that I get but both in the database and in the program I have it as an integer and only in this form does it give me an error.
This is the form I am filling out.
The strange thing is that I use the same for the other form that has foreign keys and in this form it served me well.
The professor gave us an example at the beginning of the semester where he made the code but with a smaller form, I took it and adapted it to what I needed. I hope you can help me. Thanks in advance.