having to do with machinery: a mechanical failure. 2. being a machine; operated by machinery: a mechanical toy. 3. caused by or derived from machinery: mechanical propulsion.
ERROR: cannot alter type of a column used by a view or rule DETAIL: rule _RETURN on view v_change_me depends on column too_short. Though PostgreSQL tells us which view and column prompted this error, thatâs the last favor it provides.
Computed columns can be used in select lists, WHERE clauses, ORDER BY clauses, or any other locations where regular expressions can be used, but with the following exceptions: A computed column cannot be used as a DEFAULT or FOREIGN KEY constraint definition or with a NOT NULL constraint definition.