flashback drop 閃回下降（刪除）
sql> show parameter recyclebin
sql> purge recyclebin;（清除**站）
sql> create tablespace tbs01 datafile '/home/oracle/tbs01.dbf' size 5m;
sql> create table t1 tablespace tbs01 as select * from dba_objects where rownum<=20000;
sql> create index t1_object_id_idx on t1(object_id) tablespace tbs01;
sql> select index_name from user_indexes where table_name='t1';
sql> drop table t1;
sql> select table_name from user_tables;
sql> show recyclebin
sql> select object_name, original_name, type, droptime from user_recyclebin; 包含index
sql> select count(*) from "bin$iykocy5jpo7guweaqmcbeg==$0";
sql> flashback table t1 to before drop;
sql> select index_name from user_indexes where table_name='t1';
sql> alter index "bin$lryc7ha1japguweaqmdzww==$0" rename to t1_object_id_idx; 恢復index名稱
重名的處理：
sql> flashback table "bin$iykocy5jpo7guweaqmcbeg==$0" to before drop;
sql> flashback table t1 to before drop rename to t2;
sql> drop table t1;
sql> show recyclebin 在**站中
sql> create table t2 tablespace tbs01 as select * from dba_objects where rownum<=30000;
sql> show recyclebin t1被覆蓋
sql> drop table t2 purge;
sql> purge recyclebin
flashback transaction query(閃回事務查詢)
sql> alter database add supplemental log data;
sql> alter database add supplemental log data (primary key) columns;
sql> create table t1(x int);
sql> insert into t1 values (1);
sql> commit;
sql> update t1 set x=11 where x=1; 誤操作的事務
sql> commit;
sql> insert into t1 values (2);
sql> commit;
select versions_starttime, versions_endtime, versions_xid, versions_operation, x
from t1
versions between scn minvalue and maxvalue
order by versions_starttime; 獲取誤操作事務的xid
sql> select undo_sql, operation from flashback_transaction_query where xid='02000f0059040000';
flashback database（閃回資料庫）
sql> shutdown immediate
sql> startup mount
sql> alter database flashback on; 資料庫在歸檔模式下
sql> show parameter db_flashback_retention_target
sql> select oldest_flashback_time from v$flashback_database_log;
sql> create table t1(x int);
sql> insert into t1 values (1);
sql> commit;
sql> select dbms_flashback.get_system_change_number from dual;
sql> truncate table t1;
sql> create table after_truncate(x int); 其他正確操作
sql> select oldest_flashback_time, oldest_flashback_scn from v$flashback_database_log; 確認是否在恢復範圍
sql> shutdown abort
sql> startup mount
sql> flashback database to scn 1495195;
sql> alter database open resetlogs;
sql> select * from t1;
sql> select * from after_truncate; 消失
移動資料
sqlloader
sql> create table t1(id int constraint t1_id_pk primary key, name varchar2(20), salary int constraint t1_salary_ck check(salary>0));
$ vi ~/loader.dat
100,"abc",1000
100,"def",2000
102,"xyz",-1000
em中常規匯入，自動處理違反約束的記錄
em中直接匯入
sql> select constraint_name, status from user_constraints where table_name='t1';
sql> select index_name, status from user_indexes where table_name='t1';
sql> alter table t1 enable validate constraint t1_salary_ck; 失敗
sql> @?/rdbms/admin/utlexpt1.sql
處理check約束：
sql> alter table t1 enable validate constraint t1_salary_ck exceptions into exceptions;
sql> select * from t1 where rowid in(select row_id from exceptions);
sql> update t1 set salary=abs(salary) where id=102;
sql> truncate table exceptions;
sql> alter table t1 enable validate constraint t1_salary_ck exceptions into exceptions;
處理pk約束：
sql> alter table t1 disable novalidate constraint t1_id_pk;
sql> alter table t1 enable validate constraint t1_id_pk exceptions into exceptions;
sql> select * from t1 where rowid in(select row_id from exceptions);
sql> update t1 set id=101 where name='def';
sql> truncate table exceptions;
sql> alter table t1 enable validate constraint t1_id_pk exceptions into exceptions;
sql> select index_name, status from user_indexes where table_name='t1';
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