Index '%1' for table '%2' would not be unique

Error constant SQLE_INDEX_NOT_UNIQUE
ODBC 2 State 23000
ODBC 3 State 23000
Parameter 1 Name of the index that would not be unique.
Parameter 2 Name of the table that contains the index.
Severity 16
SQLCODE –196
SQLSTATE 23505
Sybase error code 548
Probable cause

You attempted to insert or update a row that has the same value as another row in some column, and there is a constraint that does not allow two rows to have the same value in that column.