On 6/28/07, DBA Deepak <oracle.tutorials@xxxxxxxxx> wrote: Very simplified comments inline:
SQL> delete myemp; 14 rows deleted. SQL> select used_ublk,used_urec from v$session s,v$transaction t where s.taddr=t.addr and s.username='SCOTT'; USED_UBLK USED_UREC ---------- ---------- 2 14
Entire rows written to undo. SQL> update myemp set sal=sal*1.1;
14 rows updated. USED_UBLK USED_UREC ---------- ---------- 1 9
only updated column (with rowid and overhead ) written to undo SQL> insert into myemp select * from emp;
14 rows created. USED_UBLK USED_UREC ---------- ---------- 1 1
Only rowid (with overhead) written to undo. -- Jared Still Certifiable Oracle DBA and Part Time Perl Evangelist