An expression that is nullable can be turned into a nonnullable one by specifying ISNULL with the constant, where the constant is a nonnull value substituted for any NULL result.
REFERENCES permission on the type is required for computed columns based on common language runtime (CLR) user-defined type expressions.
Use large value types out of row option of sp_tableoption to store the entire LOB value out of the row. It is an identifier for the default filegroup and must be delimited, as in TEXTIMAGE_ON "default" or TEXTIMAGE_ON [default]. If the table contains FILESTREAM data and the table is partitioned, the FILESTREAM_ON clause must be included and must specify a partition scheme of FILESTREAM filegroups.
Use the COLUMNPROPERTY function with the Allows Null property to investigate the nullability of any computed column in a table.The expression cannot be a subquery or contain alias data types.Computed columns can be used in select lists, WHERE clauses, ORDER BY clauses, or any other locations in which regular expressions can be used, with the following exceptions: Based on the expressions that are used, the nullability of computed columns is determined automatically by the Database Engine.It is an identifier for the default filegroup and must be delimited, as in ON "default" or ON [default].If "default" is specified, the QUOTED_IDENTIFIER option must be ON for the current session. For more information, see SET QUOTED_IDENTIFIER (Transact-SQL).For more information, see ALTER TABLE (Transact-SQL).TEXTIMAGE_ON Indicates that the text, ntext, image, xml, varchar(max), nvarchar(max), varbinary(max), and CLR user-defined type columns (including geometry and geography) are stored on the specified filegroup.For more information, see Indexes on Computed Columns.Any computed columns that are used as partitioning columns of a partitioned table must be explicitly marked PERSISTED.is specified, the table is stored in the named filegroup. If "default" is specified, or if ON is not specified at all, the table is stored on the default filegroup.The storage mechanism of a table as specified in CREATE TABLE cannot be subsequently altered.