The SELECT Expression Can Include Data Definition Attributes
When defining a non‑updatable view, any expression in the SELECT expression list can include a data definition (Data Type, FORMAT attribute, TITLE attribute, and so on). Data definition attributes determine the form of the view display.
The data definition attributes for a view column can differ from those defined for the associated column of the underlying base tables or views. However, not all data definitions are relevant to view expressions.
For example, range constraints and DEFAULT declarations cannot be used in the expression list of a view definition. Instead, you should use the WHERE clause, or the HAVING clause if GROUP BY is specified, to define range constraints in a view definition.