Seaquel
SQL Server error code

SQL Server error 1733

SQL Server raises error 1733 at severity 16, which marks a problem with the query or data that you can correct.

Cannot create the sparse column set '%.*ls' in the table '%.*ls' because a sparse column set must be a nullable xml column. Modify the column definition to allow null values.
Msg1733
Severity16
Group1000–1999

Source: Database Engine events and errors