create table emp(deptno, sal)
as select mod(rownum,3), rownum from dual connect by level < 10;
Table created

-- Фсьуо харашо и не требует обновления, удобно, стильно, молодежно.

insert into emp
select * from emp
 where rowid in (select max(rowid) KEEP (DENSE_RANK first ORDER BY sal DESC) from emp e2 group by deptno)
 ;
3 rows inserted

-- Но тут случается "обновление колонок" и...

alter table emp add(f integer generated always as (1));
Table altered

insert into emp
select * from emp
 where rowid in (select max(rowid) KEEP (DENSE_RANK first ORDER BY sal DESC) from emp e2 group by deptno)
;
-- Упс, что-то пошло не так...
insert into emp
select * from emp
 where rowid in (select max(rowid) KEEP (DENSE_RANK first ORDER BY sal DESC) from emp e2 group by deptno)
 
ORA-54013: INSERT operation disallowed on virtual columns
 
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