Submitted by: Robert (rj1102)

Normal fields and identity fields (as of FB3) can be defined both as data type and domain.
However computed fields can only be defined as datatype.

To have a more consistent and better support of the SQL standard, I like to request that computed fields can also be defined as a domain. Above that, using domains is a good way to standarize data type usage in your database, so it is good idea to have them also available for computed fields.

For example:

SQL-2003 standard for field definition (shortened):
<column definition> ::= <column name> [ <data type> | <domain name> ]

CREATE TABLE MyTable
(
MyComputedField GENERATED ALWAYS AS (2*2), /* data type will be determined implicitly */
MyComputedField INTEGER GENERATED ALWAYS AS (2*2), /* computed field as explicit data type */
MyComputedField NumericDomain GENEARTED ALWAYS AS (2*2) /* computed field as explicit domain, -- not supported yet -- */
)