Undo 세미나
DB CAFE
- DBA { Oracle DBA 명령어 > DBA 초급 과정 > DBA 고급 과정 }
- 튜닝 { 오라클 튜닝 목록 }
- 모델링 { 데이터 모델링 가이드 }
목차
1 언두 테스트[편집]
SELECT SUBSTR(SEGMENT_NAME, 1, 20) TB , BYTES/1024/1024 "MB", BLOCKS
FROM USER_SEGMENTS
WHERE SEGMENT_NAME IN ( 'TB_BIG','TB_BIG2');
-- SHARED_POOL/BUFFER_POOL/FLASH_CACHE/BUFFER_CACHE/GLOBAL CONTEXT/PASSWORDFILE_METADATA_CACHE 키워드
alter system flush FLASH_CACHE;
alter system flush BUFFER_CACHE;
alter table tb_big rename to tb_big2;
drop table tb_big2 purge;
alter table tb_big rename to tb_big2;
SELECT A.TABLESPACE_NAME,A.STATUS, B.TOTAL_MB, A.USE_MB,
ROUND(RATIO_TO_REPORT(A.USE_MB) OVER(PARTITION BY A.TABLESPACE_NAME) * 100)||'%' AS PCT
FROM (SELECT TABLESPACE_NAME, STATUS,
ROUND(SUM(BYTES/1024/1024)) USE_MB
FROM DBA_UNDO_EXTENTS
GROUP BY TABLESPACE_NAME,STATUS
)A,
(SELECT TABLESPACE_NAME, ROUND(SUM(BYTES)/1024/1024) TOTAL_MB
FROM DBA_DATA_FILES
WHERE TABLESPACE_NAME LIKE 'UNDO%'
GROUP BY TABLESPACE_NAME
)B
WHERE A.TABLESPACE_NAME = B.TABLESPACE_NAME
ORDER BY 1,2
;
SELECT SUBSTRB(A.SEGMENT_NAME, 1, 10) AS SEGMENT_NAME
, SUBSTRB(A.TABLESPACE_NAME, 1, 10) AS TABLESPACE_NAME
, TO_CHAR(A.SEGMENT_ID, '99,999') AS SEG_ID
, TO_CHAR(A.MAX_EXTENTS, '999,999') AS MAX_EXT
, TO_CHAR(B.EXTENTS, '999,999') AS EXTENTS
, TO_CHAR(B.EXTENDS, '999,999') AS EXTENDS
, TO_CHAR((A.INITIAL_EXTENT + (B.EXTENTS - 1) * A.NEXT_EXTENT) / 1000000, '9,999.999') AS "ALLOC(MB)"
, TO_CHAR(XACTS, '9,999') AS XACTS
FROM DBA_ROLLBACK_SEGS A
, V$ROLLSTAT B
WHERE A.SEGMENT_ID = B.USN(+) ORDER BY 1;
SELECT group#
, status
, member
FROM v$logfile;
select * from V$ARCHIVED_LOG;
select * from v$parameter where name like '%log%';
alter system set log_archive_format='%t_%s_%r.arc' scope=spfile;
drop table tb_big3 purge;
create table tb_big3
as
select cola,colb,22 as colc,cold,cole,colf,colg,colh,coli
from tb_big;
select count(*) from tb_big;
alter system switch logfile;
-- 테이블 생성
CREATE TABLE TB_BIG(
COLA VARCHAR2(20), COLB NUMBER , COLC NUMBER,
COLD VARCHAR2(30), COLE VARCHAR2(30), COLF VARCHAR2(30),
COLG NUMBER , COLH VARCHAR2(30), COLI VARCHAR2(30)
);
-- DATA 입력
DECLARE
TYPE tbl_ins IS TABLE OF TB_BIG%ROWTYPE INDEX BY BINARY_INTEGER;
w_ins tbl_ins;
BEGIN
FOR i IN 1..8960000 LOOP
w_ins(i).COLA :=i;
w_ins(i).COLB :=300000;
w_ins(i).COLC :=99; -- <== 변경 테스트 대상 컬럼 99를 11로 변경
w_ins(i).COLD :='ABC'||dbms_random.string('x',10);
w_ins(i).COLE :='EEEEEEEEEEEEEEEE';
w_ins(i).COLF :='FFFFFFFFFFFFFFFF';
w_ins(i).COLG :=9999999;
w_ins(i).COLH :='HHHHHHHHHHHHHHHHHHHHHHHHHH';
w_ins(i).COLI :='IIIIIIIIIIIIIIIIIIIIIIIIII';
END LOOP;
FORALL i in 1..8960000 INSERT INTO TB_BIG VALUES w_ins(i);
COMMIT;
END;
/
-- 8,960,000 건
TB MB BLOCKS
-------------------- ---------- ----------
TB_BIG 1216 155648
1.1 UPDATE 테스트[편집]
sh-4.2$ cat update_tb_big.sql
update tb_big set colc=11;
commit;
====== 시작 ======
15:46:35 SQL> @update_tb_big.sql
8960000 rows updated.
Commit complete.
15:54:14 SQL>
====== 종료 ====== 총 7분 40초 , 460초
1.2 CTAS 테스트[편집]
sh-4.2$ cat ctas_tb_big.sql
-- rename old
alter table tb_big rename to tb_big_old;
-- ctas
create table tb_big
as
select cola,colb,22 as colc
, cold,cole,colf,colg,colh,coli
from tb_big_old;
====== 시작 ======
15:58:56 SQL> @ctas_tb_big.sql
Table created.
15:59:22 SQL>
====== 종료 ======= 총 26초
2 archive log mode 인경우 테스트[편집]
16:28:03 SQL> @update_tb_big.sql
8960000 rows updated.
Commit complete.
16:35:46 SQL>
====== 종료 ====== 총 7분 43초 , 463초
2.1 UPDATE 테스트[편집]
- 아카이빙 로그 사이즈
- 로그 테스트 전
bash-4.2# du -h
16K .
- 로그 테스트 후
-rw-r----- 1 oracle oinstall 196845056 Jun 16 16:28 arch1_37_1171284405.dbf
-rw-r----- 1 oracle oinstall 195198976 Jun 16 16:29 arch1_38_1171284405.dbf
-rw-r----- 1 oracle oinstall 194925056 Jun 16 16:29 arch1_39_1171284405.dbf
-rw-r----- 1 oracle oinstall 195596288 Jun 16 16:30 arch1_40_1171284405.dbf
-rw-r----- 1 oracle oinstall 195552256 Jun 16 16:30 arch1_41_1171284405.dbf
-rw-r----- 1 oracle oinstall 195438592 Jun 16 16:31 arch1_42_1171284405.dbf
-rw-r----- 1 oracle oinstall 189432320 Jun 16 16:31 arch1_43_1171284405.dbf
-rw-r----- 1 oracle oinstall 183622656 Jun 16 16:32 arch1_44_1171284405.dbf
-rw-r----- 1 oracle oinstall 190867456 Jun 16 16:32 arch1_45_1171284405.dbf
-rw-r----- 1 oracle oinstall 190482432 Jun 16 16:33 arch1_46_1171284405.dbf
-rw-r----- 1 oracle oinstall 190621696 Jun 16 16:33 arch1_47_1171284405.dbf
-rw-r----- 1 oracle oinstall 191492608 Jun 16 16:34 arch1_48_1171284405.dbf
-rw-r----- 1 oracle oinstall 185030144 Jun 16 16:34 arch1_49_1171284405.dbf
-rw-r----- 1 oracle oinstall 188132864 Jun 16 16:35 arch1_50_1171284405.dbf
drwxr-xr-x 1 oracle dba 4096 Jun 16 16:35 .
-rw-r----- 1 oracle oinstall 179443200 Jun 16 16:35 arch1_51_1171284405.dbf
bash-4.2# date
Sun Jun 16 16:41:50 UTC 2024
bash-4.2# du -k
2795632 .
bash-4.2# du -h
2.7G .
2.2 CTAS 테스트[편집]
bash-4.2# ls -altr
total 1358964
-rw-r--r-- 1 oracle dba 3079 May 14 2015 init.ora
drwxr-xr-x 1 oracle dba 4096 Jun 10 12:44 ..
-rw-r----- 1 oracle oinstall 24 Jun 10 12:44 lkMONGO
lrwxrwxrwx 1 oracle oinstall 54 Jun 10 13:07 spfileMONGO.ora -> /u01/app/oracle/oradata/dbconfig/MONGO/spfileMONGO.ora
lrwxrwxrwx 1 oracle oinstall 49 Jun 10 13:07 orapwMONGO -> /u01/app/oracle/oradata/dbconfig/MONGO/orapwMONGO
-rw-rw---- 1 oracle oinstall 1544 Jun 16 16:27 hc_MONGO.dat
-rw-r----- 1 oracle oinstall 198791168 Jun 16 16:49 arch1_52_1171284405.dbf
-rw-r----- 1 oracle oinstall 198788096 Jun 16 16:49 arch1_53_1171284405.dbf
-rw-r----- 1 oracle oinstall 198794240 Jun 16 16:49 arch1_54_1171284405.dbf
-rw-r----- 1 oracle oinstall 198791680 Jun 16 16:49 arch1_55_1171284405.dbf
-rw-r----- 1 oracle oinstall 198794240 Jun 16 16:49 arch1_56_1171284405.dbf
-rw-r----- 1 oracle oinstall 198794240 Jun 16 16:49 arch1_57_1171284405.dbf
drwxr-xr-x 1 oracle dba 4096 Jun 16 16:49 .
-rw-r----- 1 oracle oinstall 198789120 Jun 16 16:49 arch1_58_1171284405.dbf
bash-4.2# du -k ./
1358956 ./
bash-4.2# du -h ./
1.3G ./
3 CTAS NOLOGGING MODE[편집]
3.1 ctas nologging mode[편집]
bash-4.2# du -h
16K .
- 00:19.21 소요
-- UNRECOVERABLE 옵션 사용
SQL> @ctas_tb_big_nolog.sql
Table altered.
Elapsed: 00:00:00.03
Table created.
Elapsed: 00:00:19.21
3.2 ctas nolooging 처리후[편집]
bash-4.2# du -h
1.2G .
==> nolooging 인데도 사이즈가 크게 줄지 않음......
--- 테이블 drop 시
drop table tb_big2 purge;
bash-4.2# du -h
1.3G .
3.3 insert ~ select nologging[편집]
- 01:19 초 소요
SQL> @ins_sel_nologging.sql
Table altered.
Elapsed: 00:00:00.07
Table created.
Elapsed: 00:00:00.10
Table altered.
Elapsed: 00:00:00.04
8960000 rows created.
Elapsed: 00:01:19.94
bash-4.2# du -h
1.2G .
bash-4.2#
6 테이블스페이스 사이즈 확인[편집]
select *
from dba_tablespaces order by 1,2;
select owner,count(*)
from dba_segments where 1=1 -- owner='SYS' group by owner order by 1,2 ;
-- 테이블 생성 create table dbcafe.TB_T1(A number, B char(1),C varchar2(10))
tablespace TS_DBCAFE;
select * from dbcafe.TB_T1;
-- 세그먼트에는 테이블에 데이터가 입력된적이 없으므로 조회되지 않음. 데이터 입력시 적용됨. select *
from dba_segments where segment_name like 'TB_T%' ; -- 데이터 1건 입력
INSERT INTO dbcafe.TB_T1 VALUES (1,'1','11111'); -- commit 하지 말고 세그먼트 조회 select *
from dba_segments where segment_name like 'TB_T%' ;
-- header_file 13 -- header_block 130 -- bytes 65536 -- blocks 8 -- extents 1 -- initial_extent 65536 -- next_extent 1048576 -- relative_fno 13 select * from dba_data_files where file_id = 13; -- 테이블스페이 데이터파일 번호 // relative_fno 13 -- [데이터 입력후 아직 커밋하지 않음] -- 13 130 65536 8 1 65536 1048576
select * from v$session where status ='ACTIVE'
select rowid
, dbms_rowid.rowid_relative_fno(rowid) as file_no , dbms_rowid.rowid_block_number(rowid) as block_no
from dbcafe.TB_T1 where rownum = 1;
-- block info -- rowid file_no block_no AAAR/wAANAAAACEAAA 13 132
-- 트레이스 파일 식별자 설정 (트레이스파일을 쉽게 찾기 위해서 설정 ) alter session set tracefile_identifier ='DBCAFE_Block_Dump';
alter system dump datafile 13 block 132;
-- 트레이스 폴더로 이동 cd $ORACE_BASE/diag/rdbms/{mongo/MONGO}/trace -- DB마다 {---} 위치가 다름
-- 트레이스 파일 찾기 ls |grep DBCAFE_Block_dump;
MONGO_ora_43565_DBCAFE_Block_dump.trc <== 트레이스 파일 MONGO_ora_43565_DBCAFE_Block_dump.trm
-- 트레이스 파일 열기 vi MONGO_ora_43565_DBCAFE_Block_dump.trc
Trace file /u01/app/oracle/diag/rdbms/mongo/MONGO/trace/MONGO_ora_23904_DBCAFE_Block_Dump.trc ... 생략 ....
- 2024-06-23T03:22:44.434510+00:00 (CDB$ROOT(1))
- SESSION ID:(21.6605) 2024-06-23T03:22:44.434570+00:00
-- 21은 sid -- 6605는 serial# ..... 생략 ....
Start dump data blocks tsn: 6 file#:13 minblk 132 maxblk 132
-- 버퍼캐시 덤프 Block dump from cache: Dump of buffer cache at level 3 for pdb=1 tsn=6 rdba=54526084 BH (0x7cf64db8) file#: 13 rdba: 0x03400084 (13/132) class: 1 ba: 0x7c20a000
set: 10 pool: 3 bsz: 8192 bsi: 0 sflg: 0 pwc: 0,0 dbwrid: 0 obj: 73712 objn: 73712 tsn: [1/6] afn: 13 hint: f hash: [0x75181db8,0x75181db8] lru: [0x9afaa2c0,0x8cf53998] ckptq: [NULL] fileq: [NULL] objq: [0x6667add0,0x6667add0] objaq: [0x6667adc0,0x6667adc0] st: XCURRENT md: NULL fpin: 'ktspbwh2: ktspfmdb' fscn: 0x273bb5 tch: 2 flags: block_written_once LRBA: [0x0.0.0] LSCN: [0x0] HSCN: [0x273bb5] HSUB: [3] Printing buffer operation history (latest change first): cnt: 3 01. sid:00 L192:kcbbic2:bic:FBD 02. sid:00 L191:kcbbic2:bic:FBW 03. sid:00 L602:bic1_int:bis:FWC 04. sid:00 L822:bic1_int:ent:rtn 05. sid:00 L832:oswmqbg1:clr:WRT 06. sid:00 L930:kubc:sw:mq 07. sid:00 L913:bxsv:sw:objq 08. sid:00 L608:bxsv:bis:FBW 09. sid:00 L607:bxsv:bis:FFW 10. sid:05 L464:chg1_mn:bic:FMS 11. sid:05 L778:chg1_mn:bis:FMS 12. sid:05 L353:gcur:set:MEXCL 13. sid:05 L464:chg1_mn:bic:FMS 14. sid:05 L614:chg1_mn:bis:FBD 15. sid:05 L922:klbc:sw:cq 16. sid:05 L778:chg1_mn:bis:FMS buffer tsn: 6 rdba: 0x03400084 (13/132) scn: 0x273bb5 seq: 0x03 flg: 0x04 tail: 0x3bb50603 frmt: 0x02 chkval: 0x0e55 type: 0x06=trans data
Hex dump of block: st=0, typ_found=1 Dump of memory from 0x000000007C20A000 to 0x000000007C20C000 ........... 생략 ..............
-- 블럭 헤더 덤프 -- Itl 로우 입력한 트랜젝션 이 itl 0x01 슬롯에 저장됨 , 0x01은 1번째
select xidusn,xidslot,xidsqn from v$transaction where addr = (select taddr from v$session where sid = 21);
-- 세션 정보 조회는 TM 락 SELECT A.SID
, A.SERIAL# , C.object_name , A.SID || ', ' || A.SERIAL# AS KILL_TASK FROM V$SESSION A INNER JOIN V$LOCK B ON A.SID = B.SID INNER JOIN DBA_OBJECTS C ON B.ID1 = C.OBJECT_ID WHERE B.TYPE = 'TM' ;
-- xidusn xidslot xidsqn
4 8 1059
-- 16진수 -> 10진수로 변환
4 8 4185
0x0004.008.00000423
-- 16진수 -> 10진수로 변환 select to_number('1059', 'xxxx') from dual;
-- 10진수 -> 16진수로 변환 select to_char(1059, 'xxxx') from dual;
0x0016.026.00003222
Block header dump: 0x03400084
Object id on Block? Y seg/obj: 0x11ff0 csc: 0x0000000000273bb5 itc: 2 flg: E typ: 1 - DATA brn: 0 bdba: 0x3400080 ver: 0x01 opc: 0 inc: 0 exflg: 0 Itl Xid Uba Flag Lck Scn/Fsc
0x01 0x0004.008.00000423 0x01000614.017b.1f ---- 1 fsc 0x0000.00000000 0x02 0x0000.000.00000000 0x00000000.0000.00 ---- 0 fsc 0x0000.00000000 bdba: 0x03400084 data_block_dump,data header at 0x7c20a064
6.1 ===[편집]
tsiz: 0x1f98 hsiz: 0x14 pbl: 0x7c20a064
76543210
flag=-------- ntab=1 nrow=1 frre=-1 fsbo=0x14 fseo=0x1f8a avsp=0x1f76 tosp=0x1f76 0xe:pti[0] nrow=1 offs=0 0x12:pri[0] offs=0x1f8a block_row_dump: tab 0, row 0, @0x1f8a tl: 14 fb: --H-FL-- lb: 0x1 cc: 3 col 0: [ 2] c1 02 col 1: [ 1] 31 col 2: [ 5] 31 31 31 31 31 end_of_block_dump Block dump from disk: buffer tsn: 6 rdba: 0x03400084 (13/132) scn: 0x273bb5 seq: 0x03 flg: 0x04 tail: 0x3bb50603 frmt: 0x02 chkval: 0x0e55 type: 0x06=trans data Hex dump of block: st=0, typ_found=1 Dump of memory from 0x00007F628C33A000 to 0x00007F628C33C000 ........... 생략 ............
-- commit;
drop table dbcafe.TB_TEST purge; select * from dba_tables where owner='DBCAFE' ; select rowid , dbms_rowid.rowid_relative_fno(rowid) as file_no , dbms_rowid.rowid_block_number(rowid) as block_no
from dbcafe.TB_T1 where rownum = 1;