This is kind of rudimentary, but I'll ask it anyway. I have a table where each record is unique if at least one of three variables is different. The three variables in my case are each integers and are:
- Year
- Route
- Segment.
Now each of these individual variables allows (and has) duplicates, but if the thing is working right, no pair of records in this table should have all three of these variables with identical values. Is this table a candidate for using multiple primary keys?