I recently encountered a DB2 table that has three different indexes that are unique.
Index 1 (Columns: A, B, C)
Index 2 (Columns: A, B, C, D)
Index 3 (Columns: A, B, C, D, E)
Is the most specific one the actual unique index? Or does the definition of uniqueness differ depending about which index DB2 uses to access the table?
I'm a bit confused since, index 1 suggests that as long as my values for A, B, C are unique, I can have duplicate values for D and E. But then there's index 3 saying that A, B, C, D, E are unique, so I can't have duplicate values for D and E after all?