\u5728\u975e\u5f52\u6863\u6a21\u5f0f\u4e0b\u8868\u8bbe\u7f6e\u4e3anologging\u7528insert \/*+append*\/\u901f\u5ea6\u6700\u5feb\u3002\u90a3\u4e3a\u4ec0\u4e48\u5feb\u5462\uff0c\u539f\u7406\u662f\u4ec0\u4e48\uff1f\u4e0b\u9762\u6211\u4eec\u6765\u4e00\u8d77\u505a\u4e00\u4e2a\u5b9e\u9a8c\uff1a<\/p>\n
SQL> create or replace view m_undo_redo as
\nselect v$statname.name,value
\nfrom v$mystat, v$statname
\nwhere v$mystat.statistic# =v$statname.statistic#
\nand (v$statname.name =’redo size’
\nor v$statname.name = ‘undo change vector size’);<\/p>\n
\u89c6\u56fe\u5df2\u521b\u5efa\u3002<\/p>\n
SQL> create table t (x int);<\/p>\n
\u8868\u5df2\u521b\u5efa\u3002<\/p>\n
SQL> set timing on
\nSQL> select * from m_undo_redo;
\nNAME VALUE
\n—————————————————————- ———-
\nredo size 22644
\nundo change vector size 7484
\nSQL> insert into t select rownum from dual connect by level <=1000000;<\/p>\n
\u5df2\u521b\u5efa1000000\u884c\u3002<\/p>\n
\u5df2\u7528\u65f6\u95f4:\u00a0 00: 00: 01.03<\/p>\n
SQL> commit;<\/p>\n
\u63d0\u4ea4\u5b8c\u6210\u3002<\/p>\n
SQL> select * from m_undo_redo;
\nNAME VALUE
\n—————————————————————- ———-
\nredo size 15722456
\nundo change vector size 2380000
\nSQL> select (2380000-7484) undo,(15722456-22644) redo from dual;
\nUNDO REDO
\n———- ———-
\n2372516 15699812
\nSQL> truncate table t;<\/p>\n
\u8868\u88ab\u622a\u65ad\u3002<\/p>\n
SQL> select * from m_undo_redo;
\nNAME VALUE
\n—————————————————————- ———-
\nredo size 15781532
\nundo change vector size 2396672
\nSQL> insert \/*+append*\/ into t select rownum from dual connect by level <=1000000;<\/p>\n
\u5df2\u521b\u5efa1000000\u884c\u3002<\/p>\n
\u5df2\u7528\u65f6\u95f4:\u00a0 00: 00: 00.96<\/p>\n
SQL> commit;<\/p>\n
\u63d0\u4ea4\u5b8c\u6210\u3002<\/p>\n
SQL> select * from m_undo_redo;
\nNAME VALUE
\n—————————————————————- ———-
\nredo size 15871640
\nundo change vector size 2419196
\nSQL> select (2419196-2396672) undo,(15871640-15781532) redo from dual;
\nUNDO REDO
\n———- ———-
\n22524 90108<\/p>\n
\u4e24\u6b21\u7684\u5bf9\u6bd4\uff1a<\/p>\n
\u6a21\u5f0f
\n\u751f\u6210undo<\/p>\n
\u751f\u6210redo<\/p>\n
\u666e\u901ainsert\u00a0 2372516\u00a0 15699812
\ninsert \/*+append*\/ 22524 90108
\n\u5206\u6790\u7ed3\u8bba\uff1a\u4e24\u6b21\u5bf9\u6bd4\u7684\u7ed3\u679c\u8868\u793a\u7528insert \/*+append*\/\u540e\uff0c\u6570\u636e\u7684undo\u548credo\u6ca1\u6709\u751f\u6210\u3002\u56e0\u4e3aHWM \u5728\u79fb\u52a8\u7684\u8fc7\u7a0b\u4e2d\uff0c\u8fd9\u4e9bblock\u662f\u4e0d\u80fd\u88ab\u5176\u4ed6process\u4f7f\u7528\u7684\uff0c\u90a3\u4e48\u610f\u5473\u7740\uff0c\u53ea\u8981\u8bb0\u5f55\u4e0b\u8be5\u6b21direct insert\u6240\u6d89\u53ca\u5230\u7684\u7a7a\u95f4\u7684redo \u548c undo\u00a0 \uff0c\u5728\u5931\u8d25\u56de\u6eda\u7684\u65f6\u5019\uff0c\u53ea\u9700\u8981\u628a\u8fd9\u4e9b\u7a7a\u95f4\u4fee\u6539\u4e3a\u539f\u6765\u7684\u72b6\u6001\u5c31\u53ef\u4ee5\uff0c\u800c\u4e0d\u7528\u9010\u4e2a\u8bb0\u5f55\u53bbdelete\u3002<\/p>\n
\u539f\u6587\uff1ahttps:\/\/blog.csdn.net\/lee_sire\/article\/details\/54098275<\/p>\n","protected":false},"excerpt":{"rendered":"
\u5728\u975e\u5f52\u6863\u6a21\u5f0f\u4e0b\u8868\u8bbe\u7f6e\u4e3anologging\u7528insert \/*+append*\/\u901f\u5ea6\u6700\u5feb\u3002\u90a3\u4e3a\u4ec0\u4e48\u5feb\u5462\uff0c\u539f\u7406\u662f\u4ec0 … \u7ee7\u7eed\u9605\u8bfbORACLE-insert \/*+append*\/\u63d0\u9ad8\u6027\u80fd<\/span>