I have a table with a primary key column and 8 other columns. Each cell in the primary key column represents a physical box in a lab. Each cell in the 8 columns represents a physical connection to one of the boxes in the primary key row. I need ensure that each cell in the 8 columns has a unique value (excluding NULL), not only within it's own column and row, but compared to any cell in any column or row within the 8 columns. Is this possible to check in SQL? If so then can you please tell me how it can be done? The primary key column has a table constraint to ensure that values are unique within that column. The columns are already populated, and I need to check there uniqueness every time a cell value is updated.
Thanks,
Chris