全表更新

1.只适用于大量数据，小量数据效率比update慢

declare     type rowid_list is table of urowid index by binary_integer;     rowid_infosrowid_list;     i number;     cursor c_rowids is select rowid from t_target; begin     open c_rowids;         loop             fetch c_rowidsbulk collect into rowid_infos limit 2000;             foralli in 1..rowid_infos.count             update t_target set owner=to_char(length(owner)+1)              where rowid=rowid_infos(i);         commit;         exit when rowid_infos.count<2000;   -- 1w-5w;        end loop;     close c_rowids; end; 

2.设置nologging属性。在修改之后添加
alter table table_name logging;

3.

declare  TYPE T_MW IS TABLE OF ROWID;  T_T_MW T_MW;  CURSOR V_CUR IS    SELECT ROWID FROM t_bankdata;BEGIN  OPEN V_CUR;  LOOP    FETCH V_CUR BULK COLLECT      INTO T_T_MW LIMIT 80000;    FOR C1 IN 1 .. T_T_MW.COUNT LOOP      UPDATE t_bankdata NOLOGGING         SET msdate = '2016-02-22 11:10:10'       WHERE ROWID = T_T_MW(C1);    END LOOP;    COMMIT;    EXIT WHEN V_CUR%NOTFOUND;  END LOOP;  CLOSE V_CUR;  --COMMIT;END;