SQL> SELECT ubafil,ubablk,start_ubablk,used_ublk FROM v$transaction;
UBAFIL UBABLK START_UBABLK USED_UBLK
---------- ---------- ------------ ----------
2 1256 1229 28
SQL> conn /AS sysdba
Connected.
SQL> SELECT SUM(KTUXESIZ)
2 FROM x$ktuxe
3 WHERE KTUXEUSN=10 AND KTUXESLT=39 AND KTUXESQN=354;
SUM(KTUXESIZ)
-------------
28
SQL> SELECT 28*8192 FROM dual;
28*8192
----------
229376
从上我们可以看到该delete语句所产生的undo 大小是229376 BYTE。
摘自 love wife & love life ——Roger