Seaquel
SQL Server error code

SQL Server error 1908

SQL Server raises error 1908 at severity 16, which marks a problem with the query or data that you can correct.

Column '%.*ls' is partitioning column of the index '%.*ls'. Partition columns for a unique index must be a subset of the index key.
Msg1908
Severity16
Group1000–1999

Source: Database Engine events and errors