OG Yatra - Flashback, not just for developers

7/22/2019
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Flashback - the forgotten feature
Connor McDonald
Database Advocate
Copyright © 2018, Oracle and/or its affiliates. All rights reserved. |Copyright © 2018, Oracle and/or its affiliates. All rights reserved. |
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Copyright © 2018, Oracle and/or its affiliates. All rights reserved. |Copyright © 2018, Oracle and/or its affiliates. All rights reserved. |
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Copyright © 2018, Oracle and/or its affiliates. All rights reserved. |
Stuff
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Copyright © 2018, Oracle and/or its affiliates. All rights reserved.
etc...
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In Memoriam
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Copyright © 2019, Oracle and/or its affiliates. All rights reserved. | @connor_mc_dconnor-mcdonald.com
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flashback
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several technologies
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flashback query
flashback table
flashback drop
flashback database
flashback transaction
flashback data archive
flashback
query
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controversy
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you have always...
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.. been using flashback query
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revision
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SQL> update EMP
2 set SAL = SAL * 1.10
3 /
14 rows updated.
SQL> rollback;
Rollback complete.
how ?
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we remember stuff
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SQL> update EMP
2 set SAL = SAL * 1.10
3 /
undo header
smith $1,0001
block 2754
jones $9002
brown $1,5003
wells $2,0004
wilson $1,0005
block 2754, row 1,
sal $1000
block 2754, row 2,
sal $900
block 2754, row 3,
sal $1500
block 2754, row 4,
sal $2000
uba 5
5
$1,100
$990
$1,650
$2,200
uba 5.1uba 5.2
SQL> rollback;
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SQL> rollback;
undo header
smith $1,0001
block 2754
jones $9002
brown $1,5003
wells $2,0004
wilson $1,0005
block 2754, row 1,
sal $1000
block 2754, row 2,
sal $900
block 2754, row 3,
sal $1500
block 2754, row 4,
sal $2000
uba 5
5
$1,100
$990
$1,650
$2,200
uba 5.1uba 5.2
we can use this stuff for queries!
(Oracle version 4)
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read consistency
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select * from emp
where hiredate > '01/01/2004'
update emp set …
where empno = 1234;
Block 3217
"I need block 3217…
… as it was at 9:00"
9:00
9:03
9:05
session 1 session 2
...and time = scn
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system change number
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Session 1
Request
Block 3217,
SCN 4567192
Block 3217,
SCN 4567234
"ABC" Block 3217,
SCN 4567003,
change ABC => XYZ
undo segment block(s)
No good..too new
take a copy of the block
Locate
apply undo
Block 3217,
SCN 4567234
"ABC"
Block 3217,
SCN 4567234
"ABC"
Block 3217,
SCN 4567003
"XYZ"
Block 3217,
SCN 4567003
"XYZ"
Session 2
update emp
set ename = "ABC"
where empno = 1234;
commit;
Done !
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every query = locked at a SCN
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go back even further....
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flashback query = choose SCN
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v9
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SQL> select * from DEPT;
DEPTNO DNAME LOC
---------- -------------- -------------
10 UNKNOWN NEW YORK
20 UNKNOWN DALLAS
30 UNKNOWN CHICAGO
40 UNKNOWN BOSTON
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SQL> select * from DEPT AS OF SCN 995401;
DEPTNO DNAME LOC
---------- -------------- -------------
10 ACCOUNTING NEW YORK
20 RESEARCH DALLAS
30 SALES CHICAGO
40 OPERATIONS BOSTON
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a little less geeky
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SQL> select * from DEPT
2 AS OF TIMESTAMP systimestamp -
3 interval '20:00' minute to second;
DEPTNO DNAME LOC
---------- -------------- -------------
20 RESEARCH DALLAS
30 SALES CHICAGO
40 OPERATIONS BOSTON
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smon_scn_time
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smon_scn_time ???
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obsolete*
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more later on this
SQL> select TIMESTAMP_TO_SCN(systimestamp) from DUAL;
TIMESTAMP_TO_SCN(SYSTIMESTAMP)
------------------------------
998332
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SQL> select SCN_TO_TIMESTAMP(998314) from DUAL;
SCN_TO_TIMESTAMP(998314)
-----------------------------------------------
25-FEB-19 09.12.48.000000000 PM
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3 seconds
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SQL> select scn_to_timestamp(2409511-rownum)
2 from dual
3 connect by level <= 50;
SCN_TO_TIMESTAMP(2409511-ROWNUM)
---------------------------------------------
28-FEB-19 05.47.47.000000000 PM
28-FEB-19 05.47.47.000000000 PM
28-FEB-19 05.47.44.000000000 PM
28-FEB-19 05.47.41.000000000 PM
28-FEB-19 05.47.37.000000000 PM
28-FEB-19 05.47.34.000000000 PM
28-FEB-19 05.47.31.000000000 PM
28-FEB-19 05.47.28.000000000 PM
28-FEB-19 05.47.25.000000000 PM
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use in "normal" queries
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SQL> select e.empno, e.ename, d.dname
2 from emp e,
3 dept AS OF TIMESTAMP '23-FEB-19 11.51.02 PM' d
3 where d.deptno = e.deptno;
EMPNO ENAME DNAME
---------- ---------- --------------
7782 CLARK "PREVIOUS NAME"
7839 KING "PREVIOUS NAME"
7934 MILLER "PREVIOUS NAME"
7566 JONES RESEARCH
7902 FORD RESEARCH
7876 ADAMS RESEARCH
7369 SMITH RESEARCH
7788 SCOTT RESEARCH
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"What's in it for me?"
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1) unit testing
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SQL> select case
2 when d1.deptno is null then 'DELETE'
3 when d2.deptno is null then 'INSERT'
4 end action,
5 d1.deptno, d2.deptno, d1.dname, d1.loc
6 from DEPT d1 full outer join
7 DEPT AS OF TIMESTAMP '23-FEB-19 11.51.02 PM' d2
8 on d1.deptno = d2.deptno;
ACTION DEPTNO DEPTNO DNAME LOC
------ ---------- ---------- -------------- ----------
10 10 ACCOUNTING NEW YORK
20 20 RESEARCH DALLAS
30 30 SALES CHICAGO
DELETE 40
INSERT 50 MARKETING PERTH
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2) not just your data
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SQL> drop procedure debug_msg;
Procedure dropped.
SQL> connect / as sysdba
Connected.
SQL> select text
2 from dba_source
3 as of timestamp systimestamp - interval '5' minute
4 where name='DEBUG_MSG' order by line;
TEXT
---------------------------------------------------------------------
procedure debug_msg(m varchar2) is
begin
dbms_output.put_line(m);
dbms_application_info.set_client_info(m);
end;
5 rows selected.
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3) functional diagnosis
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DEPTNO DNAME LOC
---------- -------------- -------------
10 UNKNOWN NEW YORK
SQL> select * from DEPT
2 as of TIMESTAMP SYSTIMESTAMP -
3 INTERVAL '20:00' MINUTE TO SECOND;
DEPTNO DNAME LOC
---------- -------------- -------------
1 change ?
10 changes ?
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flashback row versions
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SQL> SELECT deptno, dname
2 FROM dept
3 VERSIONS BETWEEN
4 TIMESTAMP SYSTIMESTAMP –
5 INTERVAL '20:00' MINUTE TO SECOND
6 AND SYSTIMESTAMP
7 WHERE deptno = 10;
DEPTNO DNAME
---------- --------------
10 ACCOUNTING
10 MONEY GRABBERS
10 FINANCE
10 BEAN COUNTERS
10 UNKNOWN
1 row
5 versions
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versions_starttime
versions_startscn
versions_endtime
versions_endscn
versions_xid
versions_operation
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SQL> SELECT deptno, dname,
2 VERSIONS_STARTTIME
3 ,VERSIONS_XID
4 ,VERSIONS_OPERATION
5 FROM dept
6 VERSIONS BETWEEN
7 TIMESTAMP SYSTIMESTAMP - INTERVAL '20:00' MINUTE TO SECOND
8 AND SYSTIMESTAMP
9 WHERE deptno = 10;
DEPTNO DNAME VERSIONS_STARTTIME VERSIONS_XID V
---------- -------------- ------------------------ ---------------- -
10 UNKNOWN 03-SEP-18 11.53.45 PM 0200100060040000 U
10 MONEY GRABBERS 03-SEP-18 11.53.36 PM 0600050065040000 U
10 FINANCE 03-SEP-18 11.53.24 PM 09000D001D050000 U
10 BEAN COUNTERS 03-SEP-18 11.53.12 PM 01001A00EA030000 U
10 ACCOUNTING
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get the lot ...
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3 ,VERSIONS_XID
5 FROM dept VERSIONS BETWEEN SCN MINVALUE AND MAXVALUE;
---------- -------------- ------------------------ ---------------- -
50 UNKNOWN 03-SEP-18 11.08.15 PM 04000700EA030000 U
20 NERDS 03-SEP-18 11.07.57 PM 090016001D050000 U
20 R&D 03-SEP-18 11.07.48 PM 05000B0074040000 U
...
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grant flashback to ...
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session level
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dbms_flashback.enable_at_time(systimestamp-1);
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SQL> exec dbms_flashback.enable_at_time(
systimestamp-5/86400)
PL/SQL procedure successfully completed.
SQL> insert into T values (1);
ERROR at line 1:
ORA-08182:
operation not supported while in Flashback mode
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SQL> exec dbms_flashback.disable;
ERROR at line 1:
ORA-08184: attempting to re-enable Flashback while in Flashback
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just how far ?
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undo_retention
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SQL> show parameter undo_retention
NAME TYPE VALUE
------------------------------ ----------- --------
undo_retention integer 900
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~
SQL> desc v$undostat
Name Null? Type
----------------------------- -------- ----------------
BEGIN_TIME DATE
END_TIME DATE
...
...
TUNED_UNDORETENTION NUMBER
CON_ID NUMBER
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much much further
"no" spanning DDL
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better each version
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rewind the data, not time
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charactersets,
NLS etc
flashback
transaction
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3 ,VERSIONS_XID
5 FROM dept VERSIONS BETWEEN SCN MINVALUE AND MAXVALUE;
---------- -------------- ------------------------ ---------------- -
20 NERDS 03-SEP-18 11.07.57 PM 090016001D050000 U
20 R&D 03-SEP-18 11.07.48 PM 05000B0074040000 U
...
XID ?
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SQL> desc V$TRANSACTION
Name Null? Type
----------------------------- -------- -------
XIDUSN NUMBER
XIDSLOT NUMBER
XIDSQN NUMBER
...
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SQL> select XIDUSN, XIDSLOT, XIDSQN
2 from v$transaction
XIDUSN XIDSLOT XIDSQN
---------- ---------- ----------
1 31 674
SQL> select versions_xid from ...
VERSIONS_XID
-------------------
01 001F 00A202 0000
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SQL> desc FLASHBACK_TRANSACTION_QUERY
Name Null? Type
----------------------- -------- --------------
XID RAW(8)
START_SCN NUMBER
START_TIMESTAMP DATE
COMMIT_SCN NUMBER
COMMIT_TIMESTAMP DATE
LOGON_USER VARCHAR2(30)
UNDO_CHANGE# NUMBER
OPERATION VARCHAR2(32)
TABLE_NAME VARCHAR2(256)
TABLE_OWNER VARCHAR2(32)
ROW_ID VARCHAR2(19)
UNDO_SQL VARCHAR2(4000)
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SQL> select DNAME from dept
2 where deptno = 10;
DNAME
-------
FINANCE
SQL> select xid, undo_sql
2 from flashback_transaction_query
3 where xid = hextoraw('09000d001d050000');
XID UNDO_SQL
---------------- ------------------------------------
09000D001D050000 update "SCOTT"."DEPT"
set "DNAME" = 'BEAN COUNTERS'
where ROWID = 'AAAQ+hAAEAAAAAOAAA';
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be careful
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SQL> select text from dba_views
2 where view_name
3 = 'FLASHBACK_TRANSACTION_QUERY';
TEXT
------------------------------------------------
select
xid, start_scn, start_timestamp,
decode(commit_scn,
0, commit_scn,
281474976710655, NULL, commit_scn)
commit_scn, commit_timestamp,
logon_user, undo_change#, operation,
table_name, table_owner,
row_id, undo_sql
from SYS.X$KTUQQRY
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do not query without predicates ...
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do not forget hextoraw
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3 where xid = hextoraw('09000d001d050000');
-----------------------------------------------------
| Id | Operation | Name |
-----------------------------------------------------
| 0 | SELECT STATEMENT | |
|* 1 | FIXED TABLE FIXED INDEX| X$KTUQQRY (ind:1) |
-----------------------------------------------------
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rollback committed transaction
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three words
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delete
uh-oh...
commit
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undo a committed transaction
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SQL> BEGIN
2 DBMS_FLASHBACK.TRANSACTION_BACKOUT(
3 numtxns=>1,
4 xids=>sys.xid_array('09000D001D050000')
5 );
6 END;
7 /
BEGIN
*
ERROR at line 1:
ORA-55510: Mining could not start
ORA-06512: at "SYS.DBMS_FLASHBACK", line 37
ORA-06512: at "SYS.DBMS_FLASHBACK", line 70
ORA-06512: at line 2
'09000D001D050000'
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SQL> ALTER DATABASE ADD
2 SUPPLEMENTAL LOG DATA (PRIMARY KEY) COLUMNS;
Database altered.
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SQL> delete from DEPT
2 where DEPTNO = 10;
1 row deleted.
SQL> commit;
Commit complete.
SQL> SELECT VERSIONS_XID
2 FROM dept
3 VERSIONS BETWEEN SCN MINVALUE AND MAXVALUE;
VERSIONS_XID
----------------
080017006C040000
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SQL> BEGIN
2 DBMS_FLASHBACK.TRANSACTION_BACKOUT(
3 numtxns=>1,
4 xids=>sys.xid_array('080017006C040000')
5 );
6 END;
7 /
DEPTNO DNAME LOC
---------- -------------- ----------
20 RESEARCH DALLAS
30 SALES CHICAGO
50 MARKETING PERTH
40 HR US
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KEEP CALM
AND
DON'T PANIC
SQL> SELECT COMPENSATING_XID
2 FROM DBA_FLASHBACK_TXN_STATE
3 WHERE xid = '080017006C040000';
COMPENSATING_XID
----------------
03001C0072040000
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SQL> SELECT xid_report
2 FROM DBA_FLASHBACK_TXN_REPORT
3 WHERE compensating_xid = '03001C0072040000';
XID_REPORT
--------------------------------------------------------
<COMP_XID_REPORT XID="03001C0072040000">
<TRANSACTION XID="080017006C040000">
<UNDO_SQL>
<USQL exec="yes">
insert into "SCOTT"."DEPT"("DEPTNO","DNAME","LOC")
values ('10','ACCOUNTING','NEW YORK')
</USQL>
</UNDO_SQL>
</TRANSACTION>
<EXECUTED_UNDO_SQL>
<EXEC_USQL>
insert into "SCOTT"."DEPT"("DEPTNO","DNAME","LOC")
values ('10','ACCOUNTING','NEW YORK')
</EXEC_USQL>
</EXECUTED_UNDO_SQL>
</COMP_XID_REPORT>
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SQL> commit;
Commit complete.
SQL> select * from dept;
DEPTNO DNAME LOC
---------- -------------- ----------
20 RESEARCH DALLAS
30 SALES CHICAGO
50 MARKETING PERTH
40 HR US
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some typical restrictions
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ddl, old lobs, xml
flashback
drop
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delete
uh-oh...
commit
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three words
two
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drop
uh-oh...
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SQL> desc EMP
ERROR:
ORA-04043: object EMP does not exist
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hard
place
You are here
"undrop"
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not cool enough
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flashback table to before drop
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SQL> desc USER_RECYCLEBIN
Name Null? Type
----------------------------- -------- --------------------
OBJECT_NAME NOT NULL VARCHAR2(30)
ORIGINAL_NAME VARCHAR2(32)
OPERATION VARCHAR2(9)
TYPE VARCHAR2(25)
TS_NAME VARCHAR2(30)
CREATETIME VARCHAR2(19)
DROPTIME VARCHAR2(19)
DROPSCN NUMBER
PARTITION_NAME VARCHAR2(32)
CAN_UNDROP VARCHAR2(3)
CAN_PURGE VARCHAR2(3)
RELATED NOT NULL NUMBER
BASE_OBJECT NOT NULL NUMBER
PURGE_OBJECT NOT NULL NUMBER
SPACE NUMBER
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SQL> select OBJECT_NAME, ORIGINAL_NAME,
2 CAN_UNDROP, CAN_PURGE
3 from USER_RECYCLEBIN;
OBJECT_NAME ORIGINAL_NAME CAN CAN
-------------------------------- ------------------- --- ---
BIN$CmYCdNcITL6hp9l266nskA==$0 PK_EMP NO YES
BIN$b/W75+c/Q/CeFMBIK7cXfw==$0 EMP YES YES
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SQL> show RECYCLEBIN
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indexes / constraints / triggers
... all renamed
SQL> flashback table EMP to before drop;
Flashback complete.
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SQL> flashback table EMP to before drop
2 rename to OLD_EMP;
Flashback complete.
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indexes / constraints / triggers
... not renamed back
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how long ?
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1 second...
...10 years
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SQL> PURGE RECYCLEBIN;
SQL> PURGE TABLE emp;
SQL> PURGE TABLE "BIN$xyWe0+q+SniItJ0pn/u54A==$0";
SQL> PURGE TABLESPACE user1;
SQL> PURGE INDEX "BIN$FTX34MN88J7==$0";
SQL> PURGE TABLESPACE user1 USER fred;
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no untruncate
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flashback
table
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flashback table
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SQL> FLASHBACK TABLE DEPT
2 TO TIMESTAMP TO_TIMESTAMP('2019-06-03 12:05:00')
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"undrop"
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repeatable tests without cleanup scripts
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deletes modified rows since SCN
inserts fresh rows as of SCN
... busy
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SQL> FLASHBACK TABLE DEPT
2 TO TIMESTAMP TO_TIMESTAMP('2019-06-03 12:05:00')
3 ENABLE TRIGGERS;
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rowid's change
... enable row movement
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indexes existence unaffected
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single transaction
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... multiple tables allowed
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tables locked
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R.I must still be valid
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statistics unchanged
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most DDL is a flashback boundary
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SQL> flashback table DEPT to scn ...;
ORA-01466: unable to read data - table definition has changed
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each release gets better
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SQL> alter table DEPT add column XXX date;
SQL> desc DEPT
Name Null? Type
-------------------------- -------- --------------
DEPTNO NUMBER(2)
DNAME VARCHAR2(14)
LOC VARCHAR2(13)
XXX DATE
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ORA-08183: Flashback cannot be enabled in the middle
of a transaction
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flashback
database
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flashback database
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AUTHORISED
DATABASE
ADMINSTRATORS
ONLY !
SQL> alter database flashback on;
Database altered.
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data
changes
"new" blocks
to disk
changes
to disk
"old" blocks
to disk
redo fbdadbwr
SQL> FLASHBACK DATABASE TO '2:05PM'
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SQL> create restore point OK_SO_FAR;
...
SQL> flashback database to restore point OK_SO_FAR;
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what does it cost ?
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SQL> desc V$FLASHBACK_DATABASE_STAT
Name Null? Type
----------------------------- -------- ---------
BEGIN_TIME DATE
END_TIME DATE
FLASHBACK_DATA NUMBER
DB_DATA NUMBER
REDO_DATA NUMBER
ESTIMATED_FLASHBACK_SIZE NUMBER
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a good compromise
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guaranteed restore points
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flashback logging "optional"
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1) safer deployment
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scenario: "My New Application"
167
9:00
9:40
9:45 SQL> FLASHBACK DATABASE...
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SQL> alter table ACCOUNTS ...
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2) repeatable end to end testing
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12.2+
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flashback pluggable database
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3) production data for developers
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"hidden" example
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Data Guard
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5:00am
11:30pm
standby recovery
convert to snapshot
revert to physical
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flashback
data archive
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less flashback, more archive
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SQL> CREATE FLASHBACK ARCHIVE longterm
2 TABLESPACE space_for_archive
3 RETENTION 1 YEAR;
Flashback archive created.
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SQL> ALTER TABLE EMP FLASHBACK ARCHIVE LONGTERM;
Table altered.
[lots of DML on EMP]
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SQL> select * from EMP;
--------------------------------------------------
| Id | Operation | Name | Rows | Bytes |
--------------------------------------------------
| 0 | SELECT STATEMENT | | 14 | 518 |
| 1 | TABLE ACCESS FULL| EMP | 14 | 518 |
--------------------------------------------------
186
SQL> select * from EMP
2 AS OF TIMESTAMP SYSDATE-1/24;
--------------------------------------------------
| Id | Operation | Name | Rows | Bytes |
--------------------------------------------------
| 0 | SELECT STATEMENT | | 14 | 518 |
| 1 | TABLE ACCESS FULL| EMP | 14 | 518 |
--------------------------------------------------
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3 days later...
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SQL> select * from EMP
2 AS OF TIMESTAMP SYSDATE-3;
-----------------------------------------------------------------
| Id | Operation | Name | Rows |
-----------------------------------------------------------------
| 0 | SELECT STATEMENT | | 446 |
| 1 | VIEW | | 446 |
| 2 | UNION-ALL | | |
|* 3 | FILTER | | |
| 4 | PARTITION RANGE ITERATOR| | 445 |
|* 5 | TABLE ACCESS FULL | SYS_FBA_HIST_69539 | 445 |
|* 6 | FILTER | | |
|* 7 | HASH JOIN OUTER | | 1 |
|* 8 | TABLE ACCESS FULL | EMP | 1 |
|* 9 | TABLE ACCESS FULL | SYS_FBA_TCRV_69539 | 14 |
------------------------------------------------------------------189
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SQL> select table_name
2 from user_tables
3 /
TABLE_NAME
---------------------------
SYS_FBA_HIST_71036
SYS_FBA_TCRV_71036
SYS_FBA_DDL_COLMAP_71036
EMP
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SQL> select dbms_metadata.get_ddl(
2 'TABLE',
3 'SYS_FBA_TCRV_71036') from dual;
DDL
------------------------------------
CREATE TABLE "SCOTT"."SYS_FBA_TCRV_71036"
( "RID" VARCHAR2(4000),
"STARTSCN" NUMBER,
"ENDSCN" NUMBER,
"XID" RAW(8),
"OP" VARCHAR2(1)
)
SEGMENT CREATION IMMEDIATE
TABLESPACE "SPACE_FOR_ARCHIVE"
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SQL> select dbms_metadata.get_ddl(
2 'TABLE',
3 'SYS_FBA_HIST_71036') from dual;
DDL
------------------------------------------
CREATE TABLE "SCOTT"."SYS_FBA_HIST_71036"
( "RID" VARCHAR2(4000),
"STARTSCN" NUMBER,
"ENDSCN" NUMBER,
"XID" RAW(8),
"OPERATION" VARCHAR2(1),
"EMPNO" NUMBER(4,0), "ENAME" VARCHAR2(10),
"JOB" VARCHAR2(9), "MGR" NUMBER(4,0),
"HIREDATE" DATE, "SAL" NUMBER(7,2),
"COMM" NUMBER(7,2), "DEPTNO" NUMBER(2,0)
) COMPRESS FOR OLTP
TABLESPACE "SPACE_FOR_ARCHIVE"
PARTITION BY RANGE ("ENDSCN")
( PARTITION "HIGH_PART" VALUES LESS THAN (MAXVALUE) )
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note
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"The table does not use any of these
Flashback Data Archive reserved words
as column names:
• STARTSCN
• ENDSCN
• RID
• XID
• OP
• OPERATION"
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"I don't care what EMP looked
like last March..."
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why talk about it ?
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198
SQL> select * from EMP AS OF "JUNE";
SQL> select * from EMP AS OF "MARCH";
SQL> select * from EMP AS OF "2pm Wednesday";
SQL> select * from EMP AS OF etc etc etc
199
every historical version...
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199

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... of every row
201
sound familiar ?
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201

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202
audit history
203
we've all done it
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204
SQL> desc T
Name Null? Type
------------------------ -------- -------------
OWNER NOT NULL VARCHAR2(30)
SQL> desc T_AUDIT
Name Null? Type
------------------------ -------- --------------
AUDIT_DATE DATE
AUDIT_ACTION CHAR(1)
OWNER NOT NULL VARCHAR2(30)
205
SQL> create or replace
2 trigger AUDIT_TRG
3 after insert or update or delete on T
4 for each row
5 declare
6 v_action varchar2(1) := case when updating
7 then 'U' when deleting then 'D' else 'I' end;
8 begin
9 if updating or inserting then
10 insert into T_AUDIT
11 values (sysdate
12 ,v_action
13 ,:new.owner
14 ,:new.object_name);
15 else
16 insert into T_AUDIT
17 values (sysdate
18 ,v_action
19 ,:old.owner
20 ,:old.object_name);
21 end if;
22 end;
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206
works but slow...
207
SQL> insert into T
2 select owner, object_name
3 from all_objects
4 where rownum <= 10000;
10000 rows created.
insert into T select owner, object_name
from all_objects where rownum <= 10000
call count cpu elapsed disk query current rows
------- ------ ------- ---------- -------- --------- ---------- ----------
Parse 1 0.01 0.00 0 0 0 0
Execute 1 3.10 3.05 88 123 10642 10000
Fetch 0 0.00 0.00 0 0 0 0
------- ------ ------- ---------- -------- --------- ---------- ----------
total 2 3.12 3.06 88 123 10642 10000
INSERT INTO T_AUDIT
VALUES (SYSDATE ,:B3 ,:B1 ,:B2 )
call count cpu elapsed disk query current rows
------- ------ ------- ---------- -------- --------- ---------- ----------
Parse 1 0.00 0.00 0 0 0 0
Execute 10000 0.79 0.97 2 109 10845 10000
Fetch 0 0.00 0.00 0 0 0 0
------- ------ ------- ---------- -------- --------- ---------- ----------
total 10001 0.79 0.97 2 109 10845 10000
206
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a better, faster, robust version ...
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208
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SQL> select empno, ename, job, sal, comm,
2 nvl(VERSIONS_STARTTIME,LAST_MOD) TS
3 ,nvl(VERSIONS_OPERATION,'I') op
4 from EMP
5 versions between timestamp
6 timestamp '2019-02-11 20:12:00' and systimestamp
7 order by empno, ts;
EMPNO ENAME JOB SAL COMM TS O
---------- ---------- --------- ---------- ---------- ------------ -
7369 SMITH CLERK 806 08.10.51 PM I
7369 SMITH SALES 8060 1000 08.12.10 PM U
7499 ALLEN SALESMAN 1606 300000000 08.10.51 PM I
7521 WARD SALESMAN 1256 500000000 08.10.51 PM I
7566 JONES MANAGER 2981 08.10.51 PM I
...
7900 JAMES CLERK 956 08.10.51 PM I
7902 FORD ANALYST 3006 08.10.51 PM I
7934 MILLER CLERK 1306 08.10.51 PM I
7934 MILLER CLERK 1306 08.12.10 PM D
210
so why didn't we ?
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reason 1
212
"yeah...but who ? where ? how ?"
213
212
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SQL> alter table EMP add UPDATED_BY varchar2(10);
Table altered.
SQL> alter table EMP add UPDATED_PGM varchar2(10);
Table altered.
[etc]
214
reason 2
215
214
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separately licensed
217
216
217

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12c+ ... more options
218
1) context extension
219
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SQL> begin
2 dbms_flashback_archive.set_context_level(
3 level=> 'ALL');
4 end;
220
SQL> update EMP
2 set sal = sal*10
3 where empno = 7499;
1 row updated.
SQL> commit;
221
220
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SQL> select XID from SYS_FBA_HIST_510592;
XID
----------------
09000B00C7080000
222
SQL> set serverout on
SQL> begin
2 dbms_output.put_line(
3 dbms_flashback_archive.get_sys_context (
4 '09000B00C7080000', 'USERENV', 'SESSION_USER'));
5
8 '09000B00C7080000', 'USERENV', 'HOST'));
9
12 '09000B00C7080000', 'USERENV', 'MODULE'));
13 end;
14 /
SCOTT
WORKGROUPXPS
SQL*Plus
223
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...and a few other things :-)
224
SQL> desc SYS.SYS_FBA_CONTEXT_AUD
Name Null? Type
------------------------- -------- ------------------
XID RAW(8)
ACTION VARCHAR2(256)
AUTHENTICATED_IDENTITY VARCHAR2(256)
CLIENT_IDENTIFIER VARCHAR2(256)
CLIENT_INFO VARCHAR2(256)
CURRENT_EDITION_NAME VARCHAR2(256)
CURRENT_SCHEMA VARCHAR2(256)
CURRENT_USER VARCHAR2(256)
DATABASE_ROLE VARCHAR2(256)
DB_NAME VARCHAR2(256)
GLOBAL_UID VARCHAR2(256)
HOST VARCHAR2(256)
IDENTIFICATION_TYPE VARCHAR2(256)
INSTANCE_NAME VARCHAR2(256)
IP_ADDRESS VARCHAR2(256)
MODULE VARCHAR2(256)
OS_USER VARCHAR2(256)
225
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SQL> @pt "select * from SYS.SYS_FBA_CONTEXT_AUD
where xid = '09000B00C7080000'"
XID : 09000B00C7080000
AUTHENTICATED_IDENTITY : scott
CLIENT_IDENTIFIER :
CLIENT_INFO :
CURRENT_EDITION_NAME : ORA$BASE
CURRENT_SCHEMA : SYS
CURRENT_USER : SYS
DATABASE_ROLE : PRIMARY
DB_NAME : np12
HOST : WORKGROUPXPS
IDENTIFICATION_TYPE : LOCAL
INSTANCE_NAME : np12
MODULE : SQL*Plus
OS_USER : xpshamcdc
SERVER_HOST : xps
...
226
SQL> select empno, ename, job, sal, comm,
2 VERSIONS_XID
3 from EMP
5 timestamp '2019-02-11 20:12:00' and systimestamp
6 order by empno;
EMPNO ENAME JOB SAL COMM VERSIONS_XID
---------- ---------- --------- ---------- ---------- ----------------
7369 SMITH CLERK 806
7369 SMITH SALES 8060 1000 09001C00E04A0000
7499 ALLEN CLERK 16060 300000000 0A000A0024080000
7499 ALLEN SALESMAN 16060 300000000 09000B00C7080000
7499 ALLEN SALESMAN 1606 300000000
7521 WARD SALESMAN 1256 500000000
227
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SQL> select ...
2 from
3 ( select
4 empno, ename, job,
5 sal, comm, VERSIONS_XID
6 from EMP
8 timestamp '2019-02-11 20:12:00' and
9 systimestamp
10 ) e, SYS.SYS_FBA_CONTEXT_AUD a
11 where e.VERSIONS_XID = a.XID;
228
2) price...
230
228
230

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flashback data archive is now …
231
232
231
232

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not a typo
233
basic versus advanced
234
233
234

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112
choose your cost
compression
235
so think about FDA
236
235
236

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secure
read only
237
efficient
fdba
238
237
238

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all of your history...
239
... all of your audit
240
239
240

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"Where were you in 2004 ?!?!?"
241
dbms_flashback_archive.import_history
242
241
242

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be careful ... silent errors
243
SQL> ALTER TABLE EMP FLASHBACK ARCHIVE LONGTERM;
Table altered.
Flashback Archive:
Error ORA-1950 in SQL create table "SCOTT".SYS_FBA_DDL_COLMAP_91938
(STARTSCN NUMBER, ENDSCN NUMBER...
Flashback Archive:
Error ORA-942 in SQL insert into "SCOTT".SYS_FBA_DDL_COLMAP_91938
(ENDSCN, COLUMN_NAME, TYPE, ...
244
243
244

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flashback query
flashback table
flashback drop
flashback database
wrap up
258
248
258

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flashback query
flashback table
flashback drop
flashback database
all included in EE
260
259
260

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all cool for modern development
261
That's a wrap!
youtube bit.ly/youtube-connor
blog bit.ly/blog-connor
twitter bit.ly/twitter-connor
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