4d games are rare enough that I wouldn't have bothered to add a database column.
Since I was adding code to the footer to indicate a board's dimensions, it seemed more appropriate than treating them as 3D games.
It will probably cause confusion for new authors.
I have added tooltips to the Edit Item form, and if there are other forms they should be added to, I can do that. I have also used parentheses to make it clearer what the dimensions of a board refer to. For 3D boards, a single pair of parentheses go around the files-by-ranks part, and levels goes on its left. For 4D boards, another pair of parentheses goes around the 3D board dimensions, and the 4th dimension goes on the left. The convention I'm following places increasing dimensions on the left, and it treats the number of ranks as the first dimension. This is because in the typical Chess variant, the board has two sides, and each player starts with all his pieces on one side. So, the distance between two sides would be the number of ranks. The second dimension, the number of files, is about how much space each side has to spread out its forces. Since we normally write files before ranks in algebraic notation, it makes sense to add higher dimensions to the left side. Also, this was the convention followed in some 3D games I looked at last night. And it's also sort of how Arabic numerals work. The leftmost digit in a numeral has a higher value than those to the right.
Since I was adding code to the footer to indicate a board's dimensions, it seemed more appropriate than treating them as 3D games.
I have added tooltips to the Edit Item form, and if there are other forms they should be added to, I can do that. I have also used parentheses to make it clearer what the dimensions of a board refer to. For 3D boards, a single pair of parentheses go around the files-by-ranks part, and levels goes on its left. For 4D boards, another pair of parentheses goes around the 3D board dimensions, and the 4th dimension goes on the left. The convention I'm following places increasing dimensions on the left, and it treats the number of ranks as the first dimension. This is because in the typical Chess variant, the board has two sides, and each player starts with all his pieces on one side. So, the distance between two sides would be the number of ranks. The second dimension, the number of files, is about how much space each side has to spread out its forces. Since we normally write files before ranks in algebraic notation, it makes sense to add higher dimensions to the left side. Also, this was the convention followed in some 3D games I looked at last night. And it's also sort of how Arabic numerals work. The leftmost digit in a numeral has a higher value than those to the right.