giao trinh oracle9i

8/2/2019 Giao trinh Oracle9i

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Kin trc v qun trcsdliu Oracle

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MC LC

MC LC .................................................... ................................................ 1

CHNG 1. CC I M MI TRONG ORACLE 9I .......................................... 9

CHNG 2. CC THNH PHN KI N TRC............................................... 14 2.1. KI N TRC ORACLE SERVER........................................................................................14

2.1.1. Oracle Instance.......................................................................................................... 142.1.2. Oracle database......................................................................................................... 192.1.3. Qun tr c s dliu Oracle ....................................................................................... 232.1.4. Thit lp cc tham skhi to nh hng ti kch c b nh SGA....................................23

2.2. KT NI TI ORACLE SERVER ........ .......... ......... ......... ......... .......... ......... ......... ......... ...242.2.1. M hnh kt ni .......................................................................................................... 242.2.2. Mt skhi nim c bn lin quan n kt ni .............................................................. 252.2.3. Kt ni ti database....................................................................................................25

CHNG 3. CC CNG C QUN TR ORACLE.......................................... 27 3.1. CC CNG C QUN TR CSDLI U ORACLE......................................................273.2 . SERVER MANAGER LI NE MODE... ......... ......... .......... ......... ......... ......... ......... .......... .......2 7

3.2.1. Truy nhp Server Manager Line Mode........................................................................... 273.2.2. Phn nhm cc lnh trong Server manager ...................................................................283.2.3. Din gii cc lnh trong Server manager....................................................................... 28

3.3 . ORACLE ENTERPRI SE MANAGER....... ......... ......... .......... ......... ......... ......... .......... ......... .29 3.3.1. Kin trc OME............................................................................................................ 293.3.2. Cc dch v chung ...................................................................................................... 303.3.3. Oracle Configuration Assistant .....................................................................................30

3.3.4. Oracle Enterprise Manager Console .............................................................................. 303.4. CC CNG C QUN TR KHC....................................................................................31

CHNG 4. TO DATABASE................................................... ................... 32 4.1. CC BC TO DATABASE...........................................................................................324.2 . CHUN B MI TRNG..............................................................................................32

4.2.1. Chun b hiu hnh................................................................................................ 324.2.2. Ln khoch btr cc file thng tin............................................................................ 324.2.3. Optimal Flexible Architecture OFA.............................................................................. 334.2.4. Cu trc thmc phn mm Oracle ............................................................................. 344.2.5. Bin mi trng......................................................................................................... 34

4.3 . CHUN B CC THAM S TRONG PARAMETER FI LE ......... .......... ......... ......... ......... ......35

4.4 . CHUN B I NSTANCE PHC V QUN TR ...................................................................36 4.4.1. To mt instance ....................................................................................................... 364.4.2. Khi ng instance..................................................................................................... 374.4.3. Dng instance............................................................................................................ 374.4.4. Hu instance.............................................................................................................. 38

4.5. TO DATABASE.............................................................................................................38 4.5.1. Khi ng Instance .................................................................................................... 384.5.2. Lnh to database...................................................................................................... 384.5.3. Oracle Database Assistant........................................................................................... 404.5.4. File script v d to mt database................................................................................. 404.5.5. Li xy ra khi to database.......................................................................................... 41

4.5.6. Kt qu sau khi to database....................................................................................... 414.6. TO DATA DI CTI ONARY CHO DATABASE.... .......... ......... ......... ......... .......... ......... .........42


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CHNG 5. QUN TR ORACLE DATABASE.......... ...... ..... ...... ..... ...... ...... ... 43 5.1 . PHN LOI USERS........................................................................................................43

5.1.1. Database Administrators ............................................................................................. 435.1.2. Security Officers......................................................................................................... 435.1.3. Application Developers................................................................................................ 445.1.4. Database Users.......................................................................................................... 445.1.5. Network Administrators............................................................................................... 44

5.2. PHNG THC XC NHN C QUYN TRUY NHP...................................................445.2.1. Phng thc xc nhn quyn ...................................................................................... 445.2.2. Xc nhn quyn bi hiu hnh ................................................................................ 455.2.3. Xc nhn quyn bng file mt khu.............................................................................. 465.2.4. Thay i mt khu internal.......................................................................................... 46

5.3. TO PARAMETER FILE...... ......... ......... .......... ......... ......... ......... .......... ......... ......... .........47 5.3.1. Sdng cc tham s.................................................................................................. 475.3.2. Mt squy tc i vi cc tham s............................................................................... 485.3.3.................................................................................................................................. 485.3.4. Cc tham sc bn....................................................................................................48

5.4 . START V SHUT DOWN DATABASE ......... .......... ......... ......... ......... ......... .......... ......... ....49

5.4.1. Cc bc Start v Shut down database......................................................................... 495.4.2. Start database ........................................................................................................... 515.4.3. Thay i tnh sn dng ca database hin thi .............................................................. 515.4.4. Shut down database...................................................................................................525.4.5. Thay i trng thi ca database ................................................................................. 535.4.6. Tm treo v phc hi Database ...................................................................................545.4.7. t ch hot ng tnh cho database....................................................................... 55

5.5. T TRNG THI TNH CHO DATABASE......................................................................555.5.1. a Database vo trng thi tnh.................................................................................555.5.2. Phc hi h thng tr li hot ng nhbnh thng..................................................... 565.5.3. Xem trng thi ca database....................................................................................... 56

5.6. LY CC THNG TI N V H THNG.............................................................................56

5.6.1. Mt sviews cn quan tm ......................................................................................... 575.6.2. Hin th gi tr ca cc thng sh thng ..................................................................... 575.6.3. Tham sh thng ng (c ththay i) ..................................................................... 585.6.4. Qun l session..........................................................................................................585.6.5. Trace file v ALERT file ............................................................................................... 59

CHNG 6. DATA DI CTI ONARY, VI EWS V PACKAGES............................ 60 6.1 . DATA DI CTI ONARY V VI EWS .....................................................................................60

6.1.1. Data Dictionary .......................................................................................................... 606.1.2. Data Dictionary views ................................................................................................. 616.1.3. Sripts qun tr ............................................................................................................ 63

6.2. STORED PROCEDURES V CC PACKAGES CHUN......................................................646.2.1. Gii thiu chung......................................................................................................... 646.2.2. Stored procedures ...................................................................................................... 646.2.3. Packages chun ......................................................................................................... 656.2.4. Gii thiu mt spackages chun do Oracle cung cp.................................................... 656.2.5. Package DBMS_METADATA .......................................................................................... 676.2.6. Package dbms_redefinition..........................................................................................68

6.3 . THNG TI N V CC STORED PROCEDURES ......... ......... ......... ......... .......... ......... ......... .68

CHNG 7. QUN TR CONTROL FI LES.................................................... 71 7.1 . CONTROL FI LES............................................................................................................71

7.1.1. Gii thiu control file................................................................................................... 71

7.1.2. Cch thc t tn control file....................................................................................... 717.1.3. Kt hp nhiu control files........................................................................................... 717.1.4. Ni dung ca control file ............................................................................................. 727.1.5. Cc tham snh hng ti kch thc ca control file.................................................... 73


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7.2 . QUN TR CONTROL FILE........ .......... ......... ......... ......... .......... ......... ......... ......... .......... .73 7.2.1. To mi control file..................................................................................................... 737.2.2. To mi control file cho mt database c sn............................................................757.2.3. Mt s li i vi cc Control Files................................................................................ 757.2.4. Hu b Control Files ................................................................................................... 76

7.3 . THNG TI N TRNG THI CA CONTROL FILES ........ .......... ......... ......... ......... .......... ....77

CHNG 8. QUN L REDO LOG FI LES .................................................... 78 8.1. SDNG CC REDO LOG FI LES......... .......... ......... ......... ......... .......... ......... ......... .........78

8.1.1. Redo log file .............................................................................................................. 788.1.2. Online Redo Log Groups.............................................................................................. 788.1.3. Online Redo Log Members........................................................................................... 788.1.4. Ni dung ca Online Redo Log Files (Members) ............................................................. 798.1.5. Active v Inactive Online Redo Log Files ....................................................................... 798.1.6. Thit lp cc Redo Log Files khi to............................................................................ 79

8.2 . LGWR, LOG SWI TCHES V CHECKPOI NTS.... .......... ......... ......... ......... .......... ......... .......8 08.2.1. Redo Log Buffer v Background process LGWR.............................................................. 808.2.2. Log Switches ............................................................................................................. 80

8.2.3. Checkpoints............................................................................................................... 81

8.3 . LN KHOCH SDNG REDO LOG FILES................. .......... ......... ......... ......... .......... ..818.3.1. Xc nh slng Online redo log files ......................................................................... 818.3.2. Ni t cc Online Redo Log Files ................................................................................ 818.3.3. Xc nh kch thc cho cc Online Redo Log Files......................................................... 828.3.4. Lu trcc redo log files............................................................................................. 82

8.4. IU KHI N LU TRSAU I VI PRI MARY/ STANDBY ..........................................83 8.4.1. Thit lp tham sARCHIVE_LAG_TARGET.....................................................................838.4.2. Cc yu tnh hng ti tham sARCHIVE_LAG_TARGET.............................................84

8.5 . XC NH CH LU TR........................................................................................84 8.5.1. Sdng lnh Server Manager...................................................................................... 848.5.2. Sdng thng tin trong data dictionary........................................................................ 85

8.6. IU KHI N CC LOG SWI TCHS V CHECKPOI NTS .......... ......... ......... ......... .......... .....86 8.6.1. Thc hin log switches................................................................................................868.6.2. Thc hin checkpoint..................................................................................................868.6.3. iu chnh cc ngt qung checkpoints......................................................................... 86

8.7 . QUN TR CC REDO LOG FI LES.......... .......... ......... ......... ......... .......... ......... ......... .......87 8.7.1. B sung cc online redo log groups.............................................................................. 878.7.2. B sung cc online redo log members........................................................................... 888.7.3. nh li ch cho cc redo log file.................................................................................. 888.7.4. Ngng sdng cc Online redo log groups...................................................................898.7.5. Ngng sdng cc Online redo log members................................................................ 908.7.6. Xo rng Online redo log file ....................................................................................... 91

CHNG 9. QUN TR TABLESPACES V DATA FI LES ..... ...... ...... ..... ...... .. 92 9.1. CU TRC CA DATABASE...........................................................................................92

9.1.1. Quan h gia database vi cc tablespaces v data files................................................. 929.1.2. Quan h gia segment vi cc extent v cc blocks ....................................................... 93

9.2 . PHN LOI CC TABLESPACES ......... .......... ......... ......... ......... .......... ......... ......... .........94 9.2.1. Tablespace SYSTEM v non-SYSTEM ............................................................................ 949.2.2. Tablespaces read-only / read-write............................................................................... 959.2.3. Temporary tablespace / permanent tablespace .............................................................. 95

9.3 . QUN L KHNG GI AN TRONG TABLESPACES.............. .......... ......... ......... ......... ..........96 9.3.1. Dictionary-Managed Tablespaces.................................................................................. 969.3.2. Locally-Managed Tablespaces ...................................................................................... 96

9.4. THIT LP TRNG THI CHO TABLESPACES............ ......... ......... .......... ......... ......... ......979.5 . TRAO I CC TABLESPACES GIA DATABASES.........................................................97

9.5.1. Mt shn chtrong vic trao i cc tablespace: ........................................................ 98


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9.5.2. Cc bc thc hin chuyn i mt tablespace gia cc database................................... 989.6. TO TABLESPACE ........ .......... ......... ......... ......... .......... ......... ......... ......... ......... .......... ....99

9.6.1. Lnh to tablespace.................................................................................................... 999.6.2. Ch qun l cc tablespaces.................................................................................. 1019.6.3. To temporary tablespace......................................................................................... 1019.6.4. Cc tham s lu tr.................................................................................................. 101

9.7. CC THAY I I VI TABLESPACE....................................................................... 1029.7.1. Chuyn i mt tablespace thnh mt temporary tablespace ........................................ 1029.7.2. Thm mi cc tablespace.......................................................................................... 1029.7.3. M rng data files .................................................................................................... 1039.7.4. Thay i kch thc data file...................................................................................... 1039.7.5. Chuyn i ch ONLINE v OFFLINE...................................................................... 1049.7.6. Di chuyn cc data file.............................................................................................. 1059.7.7. Tablespace chc ................................................................................................... 1069.7.8. Hu tablespace ........................................................................................................ 106

9.8 . THNG TI N V CC TABLESPACES.... ......... .......... ......... ......... ......... .......... ......... ....... 10 79.8.1. Xem thng tin tablespace.......................................................................................... 1089.8.2. Xem thng tin data files............................................................................................ 108

CHNG 10 . CU TRC LU TR........................................................... 110 10 .1. CC LOI SEGMENTS .............................................................................................. 110

10.1.1. Table .................................................................................................................... 11010.1.2. Table partition........................................................................................................ 11010.1.3. Cluster .................................................................................................................. 11010.1.4. Index .................................................................................................................... 11010.1.5. Index-Organized Table............................................................................................ 11110.1.6. Index Partition ....................................................................................................... 11110.1.7. Rollback Segment ................................................................................................... 11110.1.8. Temporary Segment ............................................................................................... 11110.1.9. LOB Segment......................................................................................................... 11110.1.10. LOB Index............................................................................................................ 112 10.1.11. Nested Table........................................................................................................ 11210.1.12. Bootstrap Segment ............................................................................................... 112

10.2. QUN L EXTENTS................................................................................................... 11210.2.1. Cp pht v thu hi cc extents ............................................................................... 11210.2.2. Sdng v gii phng cc extent............................................................................. 11310.2.3. Kt hp cc vng khng gian trng .......................................................................... 113

10 .3. BLOCK DLI U ....................................................................................................... 11510.3.1. Cu trc ca block dliu ....................................................................................... 11510.3.2. Cc tham ssdng khng gian trong block............................................................. 11610.3.3. Sdng khng gian trong block............................................................................... 11710.3.4. Phn loi mc phn on i vi tng loi segment .............................................. 117

10.4. THNG TI N V CU TRC LU TR........................................................................ 11810.4.1. Cc view lu trthng tin ....................................................................................... 11810.4.2. Xem thng tin v cc segments................................................................................ 11910.4.3. Thng tin v cc extents ......................................................................................... 12010.4.4. Thng tin v cc vng trng .................................................................................... 121

CHNG 11. QUN L ROLLBACK SEGMENTS........ ...... ...... ..... ...... ..... .... 122 11.1. GII THI U ROLLBACK SEGMENTS ........................................................................ 122

11.1.1. Khi nim .............................................................................................................. 12211.1.2. Mc ch sdng segment...................................................................................... 12211.1.3. Phn loi rollback segment ...................................................................................... 123

11.2. SDNG ROLLBACK SEGMENT............. ......... .......... ......... ......... ......... ......... .......... . 12 411.2.1. Sdng rollback segment trong cc transaction......................................................... 12411.2.2. Tng trng i vi cc rollback segments ................................................................ 12511.2.3. Ti u cc rollback segments ................................................................................... 126


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11.3. QUN L ROLLBACK SEGMENTS ............................................................................. 12611.3.1. Sdng rollback segment ....................................................................................... 12611.3.2. To rollback segment.............................................................................................. 12711.3.3. Thay i trng thi ca Rollback segments................................................................ 12811.3.4. Instance sdng rollback segment........................................................................... 12911.3.5. iu chnh kh nng lu trca rollback segment ..................................................... 12911.3.6. Gim bt rng ca rollback segment .................................................................... 129

11.3.7. Hy b rollback segment......................................................................................... 13011.3.8. Qun l undo tng............................................................................................. 13011.4. THNG TI N V CC ROLLBACK SEGMENT.............. .......... ......... ......... ......... ......... ... 13 1

11.4.1. Xem thng tin chung v cc rollback segment............................................................ 13111.4.2. Xem thng tin thng k v rollback segment ............................................................. 13211.4.3. Thng tin v rollback segment ang active................................................................ 133

11 .5. CC VN LI N QUAN TI ROLLBACK SEGMENT................................................ 13411.5.1. Thiu khng gian cho cc transactions...................................................................... 13411.5.2. Li c dliu khng ng nht .............................................................................. 13411.5.3. Chn session.......................................................................................................... 135

CHNG 12. QUN L TEMPORARY SEGMENTS....... ..... ...... ..... ...... ..... ... 137 12 .1. TEMPORARY SEGMENTS......... ......... ......... .......... ......... ......... ......... ......... .......... ....... 13 7

12.1.1. Phn loi temporary segments................................................................................. 13812.1.2. Sdng cc Sort Segments..................................................................................... 13912.1.3. Sort Extent Pool ..................................................................................................... 139

12.2. CP PHT KHNG GI AN CHO TEMPORARY SEGMENT......... ......... ......... ......... ........ 139 12.3. THNG TI N V CC TEMPORARY SEGMENT.......... ......... ......... ......... .......... ......... .... 14 0

CHNG 13. CLUSTERS V I NDEX-ORGANI ZED TABLES..... ...... ...... ..... .. 142 13.1. TNG QUAN V CLUSTERS V I NDEX-ORGANI ZED TABLES......... ......... .......... ....... 14 2

13.1.1. Cluster .................................................................................................................. 14313.1.2. Xem xt v chn la Cluster .................................................................................... 144

13.1.3. Cc kiu cluster...................................................................................................... 14413.1.4. Chn la kiu cluster .............................................................................................. 145

13.2. QUN L CLUSTER................................................................................................... 14613.2.1. To cluster............................................................................................................. 14613.2.2. To Hash Cluster.................................................................................................... 14813.2.3. Xc nh gi tr SIZE cho cluster............................................................................... 14913.2.4. Cc tham schnh cho hash cluster ...................................................................... 14913.2.5. Sa i cc Cluster................................................................................................. 15013.2.6. Xo Cluster ............................................................................................................ 151

13.3. THNG TI N V CC CLUSTERS.......... ......... ......... ......... ......... .......... ......... ......... ...... 15 313.3.1. Xc nh Cluster v cc ct kho Cluster ................................................................... 15313.3.2. Ly thng tin ct kho ca cluster v cc ct trong bng ............................................ 15413.3.3. Ly thng tin cho hash cluster.................................................................................. 154

13.4. I NDEX-ORGANI ZED TABLE...................................................................................... 15513.4.1. Tnh cht chung ..................................................................................................... 15513.4.2. To mt index-organized table................................................................................. 15613.4.3. Hin tng ROW OVERFLOW (trn dng dliu)....................................................... 15813.4.4. Ly thng tin IOT (Index Orrganized Table).............................................................. 159

CHNG 14. QUN L CC TABLES................................................. ....... 160 14.1. TNG QUAN V TABLES........................................................................................... 160

14.1.1. Phn loi cc tables ................................................................................................ 16014.1.2. Cu trc cc dng dliu (row data) ........................................................................ 160

14 .2. CC KI U DLI U TRONG TABLE........................................................................... 16114.2.1. Kiu dliu v hng............................................................................................. 16114.2.2. Tp hp (collection)................................................................................................ 16514.2.3. Kiu quan h (REF)................................................................................................. 166


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14.2.4. Kiu dliu TIMESTAMP ......................................................................................... 16614.3. QUN L CC TABLES.............................................................................................. 166

14.3.1. To table............................................................................................................... 16614.3.2. Thit lp gi tr PCTFREE v PCTUSED ...................................................................... 16814.3.3. Migration (di tr) v Chaining cc dng dliu .......................................................... 16914.3.4. Sao chp mt tables ............................................................................................... 16914.3.5. Qun tr columns trong table.................................................................................... 170

14.3.6. Chuyn mt Table ti Segment hay Tablespace mi ................................................... 17214.3.7. nh ngha li mt table ang online......................................................................... 17214.3.8. Bng ngoi External table ..................................................................................... 174

14 .4. CC RNG BUC (CONSTRAI NTS) I VI TABLES .............................................. 17514.4.1. Rng buc i vi tables ......................................................................................... 17514.4.2. Null / Not Null ........................................................................................................ 17514.4.3. Unique .................................................................................................................. 17614.4.4. Primary Key ........................................................................................................... 17614.4.5. Foreign Key ( Referential Key).................................................................................. 17614.4.6. Check.................................................................................................................... 177

14.5. QUN L KHNG GIAN LU TRTRONG TABLE..................................................... 17714.5.1. Thay i thng tin lu trv tham ssdng Block.................................................. 17714.5.2. Cp pht cc extents bng tay (manually)................................................................. 17814.5.3. High Water Mark .................................................................................................... 17914.5.4. Thu hi khng gian khng sdng........................................................................... 18014.5.5. Truncate mt table ................................................................................................. 18114.5.6. Xo table............................................................................................................... 18114.5.7. Kim tra cu trc bng............................................................................................ 18214.5.8. Pht hin cc rows b migration................................................................................ 182

14.6. THNG TI N V TABLES............................................................................................ 18314.6.1. Thng tin chung v cc tables.................................................................................. 18314.6.2. Thng tin v sdng block v thng tin chaining....................................................... 184

CHNG 15. QUN L CC I NDEXES ..................................................... 185 15.1. PHN LOI I NDEXES............................................................................................... 185

15.1.1. Index trn mt column v Index trn nhiu columns .................................................. 18515.1.2. Unique index v Non-unique index............................................................................ 18515.1.3. Partitioned index v non-partitioned index................................................................. 185

15.2. T CHC I NDEX ...................................................................................................... 18515.2.1. B-TREE index ......................................................................................................... 18515.2.2. Reverse Key Index.................................................................................................. 18715.2.3. Bitmap Index ......................................................................................................... 18815.2.4. So snh gia B-TREE index v Bitmap index.............................................................. 189

15.3. QUN L I NDEX....................................................................................................... 18915.3.1. To cc index......................................................................................................... 189

15.3.2. Mt scch sdng index ...................................................................................... 19215.3.3. To Index kho ngc (reverse key index)................................................................ 19315.3.4. To Bitmap index ................................................................................................... 19315.3.5. Thay i tham s lu trcho index .......................................................................... 19415.3.6. Cp pht v thu hi khng gian sdng ca index..................................................... 19415.3.7. Xy dng li (Rebuild) cc index .............................................................................. 19515.3.8. Kim tra tnh hp l ca index.................................................................................. 196 15.3.9. Xo cc index......................................................................................................... 197

15.4. THNG TI N V CC I NDEX...................................................................................... 19715.4.1. Xem thng tin v cc index...................................................................................... 19715.4.2. Tm cc ct trong mt index .................................................................................... 198

CHNG 16 . NP V T CHC LU TRDLI U.................................. 199 16.1. GII THI U CHUNG ................................................................................................ 199

16.1.1. Tng quan vic np dliu...................................................................................... 199


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16.1.2. Np d liu trc tip............................................................................................... 20016.2. NP DLI U ........................................................................................................... 200

16.2.1. Np d liu bng SQL* Loader................................................................................. 20016.2.2. Phng php np dliu ........................................................................................ 20216.2.3. So snh hai phng php np dliu....................................................................... 20316.2.4. Np d liu ng thi (Parallel direct load)................................................................ 204

16.3. NP DLI U BNG SQL* LOADER........................................................................... 20616.3.1. Sdng SLQ*LOADER............................................................................................ 20616.3.2. Parameter file (tp tham s) .................................................................................... 20716.3.3. Control file (tp iu khin) ..................................................................................... 20816.3.4. Data file ................................................................................................................ 21016.3.5. Cc thnh phn ca log file...................................................................................... 21016.3.6. Cc file u ra khc ................................................................................................ 21016.3.7. Cc hng dn khi sdng load ............................................................................. 211

16.4. T CHC LI DLI U BNG CNG C EXPORT V I MPORT ................................. 21216.4.1. Cng c dch chuyn dliu .................................................................................... 21216.4.2. Cc ch Export .................................................................................................. 21316.4.3. Export dliu trc tip v Export dliu thng thng.............................................. 214

16 .5. CNG C EXPORT.................................................................................................... 215

16.5.1. Sdng cng c Export ......................................................................................... 21516.5.2. Gii thiu mt sch export ............................................................................... 21716.5.3. Cc tablespaces trao i.......................................................................................... 21916.5.4. Mt sthng bo khi export: Warning, Error, v Completion Messages......................... 219

16 .6. CNG C I MPORT ................................................................................................... 22016.6.1. Sdng cng c Import.......................................................................................... 22016.6.2. Chuyn i character set......................................................................................... 224

CHNG 17. QUN L USER ................................................... ............... 225 17.1. USER TRONG DATABASE ......................................................................................... 225

17.1.1. User v nhng thnh phn lin quan ........................................................................ 225

17.1.2. Database schema ................................................................................................... 22617.2. QUN L USER ........................................................................................................ 226

17.2.1. Cc bc thc hin khi to mi user......................................................................... 22617.2.2. To mi user vi c chxc nhn bi database ......................................................... 22717.2.3. Thay i thuc tnh ca user.................................................................................... 22817.2.4. Thay i hn mc (quota) sdng tablespace........................................................... 22817.2.5. Hu User ............................................................................................................... 229

17.3. THNG TI N V USER ............................................................................................... 229

CHNG 18. QUN L THNG TI N PROFI LES................................. ....... 231 18.1. GII THI U PROFI LE.............................................................................................. 231

18.2. QUN L PROFI LE................................................................................................... 23218.2.1. To Profile ............................................................................................................. 23218.2.2. Thit lp cc gii hn v ti nguyn.......................................................................... 23318.2.3. Gn Profile cho User ............................................................................................... 23318.2.4. t gii hn ti nguyn........................................................................................... 23418.2.5. Thay i thng tin trong profile................................................................................ 23418.2.6. Hu profile............................................................................................................. 23518.2.7. Thng tin v cc gii hn ti nguyn ........................................................................ 235

18.3. QUN L MT KHU................................................................................................ 23618.3.1. To profile qun l mt khu ................................................................................... 23718.3.2. Cc tham siu chnh mt khu............................................................................. 23818.3.3. Mt sc im chnh trong qun l mt khu.......................................................... 238

18.3.4. Hm cung cp mt khu cho ngi sdng.............................................................. 23918.3.5. Thng tin v mt khu............................................................................................ 239

CHNG 19. CC QUYN H THNG...................................................... 241


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19.1. PHN LOI QUYN .................................................................................................. 24119.1.1. Cc quyn h thng................................................................................................ 24119.1.2. Gn cc quyn h thng.......................................................................................... 24119.1.3. Xc nhn user bng password file ........................................................................... 24219.1.4. Thng tin v cc quyn ........................................................................................... 243

19.2. QUN L QUYN...................................................................................................... 24419.2.1. Thu hi cc quyn h thng..................................................................................... 244

19.2.2. Quyn trn cc i tng........................................................................................ 24519.2.3. Gn cc quyn trn i tng.................................................................................. 24619.2.4. Thng tin v cc quyn ........................................................................................... 24619.2.5. Thu hi cc quyn trn i tng............................................................................. 247

CHNG 20. QUN L CHC DANH (ROLE) ........................................... 249 20.1. CHC DANH (ROLE) TRONG DATABASE................. .......... ......... ......... ......... .......... . 249

20.1.1. Cc tnh cht ca chc danh .................................................................................... 24920.1.2. Li ch ca vic sdng chc danh .......................................................................... 249

20.2. QUN L CHC DANH ............................................................................................. 25020.2.1. To v sa cha cc Chc danh............................................................................... 250

20.2.2. Cc chc danh c nh ngha sn ......................................................................... 250

20.2.3. Sa cha cc chc danh.......................................................................................... 25120.2.4. Gn cc chc danh ................................................................................................. 25220.2.5. Thit lp chc danh mc nh .................................................................................. 25220.2.6. Enable v Disable cc chc danh.............................................................................. 25320.2.7. Thu hi cc chc danh tcc user ........................................................................... 25420.2.8. Xo cc chc danh.................................................................................................. 254

20.3. THNG TI N V CC CHC DANH............................................................................. 254

CHNG 21. T NH NNG H TRNGN NGQUC GI A ...................... 256 21.1. NGN NGQUC GI A ............................................................................................. 256

21.1.1. Cc c im chnh................................................................................................. 256

21.1.2. Chn tp k tcho database .................................................................................... 25621.1.3. Tp k tv tp k tquc gia ca database.............................................................. 25721 .2. CC THAM S NLS................................................................................................... 258

21.2.1. La chn tham s................................................................................................... 25821.2.2. Ngn ngph thuc v gi tr territory mc nh ....................................................... 25921.2.3. Xc nh cc bin mi trng................................................................................... 25921.2.4. Chnh c trng ngn ng(Language-Dependent) cho tng session......................... 26021.2.5. Tham sNLS v cc hm SQL.................................................................................. 261

21.3. THNG TI N V CC GI TR NLS C KHI TO ................................................ 26321.3.1. Thng tin v tp k tsdng................................................................................ 26321.3.2. Thng tin v cc thit lp thng sNLS .................................................................... 263

PH LC........................................... ...................................................... 266 A TI LIU THAM KHO............................................................. Error! Bookmark not defined.B DANH MC CC H NH V........................................................................................... 266


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Chng 1. CC IM MI TRONG ORACLE 9i

Phin bn Oracle9iRelease 1 (9.0.1) c a ra th trng vo u nm 2001 v c citin, b sung thm mt s chc nng, c im mi. Cc c im ny lm cho vicqun l database tr nn mm do, linh hot v hiu qu hn. Di y, ta s xem xt mt

sc im mi ny:

Cho php nh ngha li cu trc ca tables ang online

Chc nng ny c cung cp trong gi package DBMS_REDEFINITION do Oracle cungcp, cho php ngi dng c thnh ngha li cu trc ca mt table thng quan cu lnhDML ngay khi n ang online. Vi cc phin bn trc, Oracle 8i, ta cng c thnh nghali cu trc ca table nhng trc cn phi t ch offline cho n. iu ny khngthun tin cho vic qun tr.

Cho php t hc hin lnhANALYZE VALIDATE STRUCTURE tc t hiC ththc hin lnh ANALYZEti u table ngay c khi ang c lnh DML thc hin trntable.

iu khin lu t rsau

Oracle cung cp c chiu khin switching i vi cc online redo log group da theo thigian (time-based). Trong cu hnh primary/standby, tt c cc noncurrent logs tiprimary site sc lu tr ri vn chuyn ti standby database. Vic ny s hiu qu khihn chslng cc redo records.

Tm t reo database

Oracle9i cung cp chc nng suspend/resume. Qun tr vin s dng lnh ALTERSYSTEM SUSPEND tm treo database, dng mi thao tc truy xut vo ra i vi ccdatafiles v control files. Khi database trng thi tm treo, cc thao tc vo ra (I/Ooperations) ang thc hin sc kt thc v nhng truy cp vo database mi phtsinh sc y vo queue. Thc hin lnh ALTER SYSTEM RESUMEkhi phc li tnhtrng bnh thng ca database.

t ch hot ng tnh cho databaseOracle9icho php a database vo ch hot ng tnh(quiesced state). Theo ch ccc DBA transactions, queries, v cc lnh PL/SQL l c php thc hin. Trng thi nycho php ngi dng thc hin cc thao tc qun tr mt cch an ton. Sdng cu lnhALTER SYSTEM QUIESCE RESTRICTEDa database v ch hot ng tnh.

Kh nng khi phc v cp pht li khng gian

Oracle s tng thc hin tm treo (suspending) v sau khi phc (resuming) li victhc hin cc thao tc database tn km (large database operations) trong trng hp c li

cp pht khng gian. Nh vy m Oracle database server s c thtthc hin cc thao tchp l thay v vic tr v thng bo li nh cc phin bn trc. Sau khi cc li ny ckhc phc database li c tng khi phc bnh thng.


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Cho php lu t rtr n nhiu ch lu t r

S lng ch lu tr ti a m ta c thsdng lu trcc online redo log c tngln t5 ti 10.

Tng qun l vng khng gian

Oracle9icho php qun l tng vic gii phng v sdng cc vng khng gian c trongcc segments c lu tr trong cc locally managed tablespaces thng qua vic s dngmnh SEGMENT SPACE MANAGEMENT c trong cu lnh CREATE TABLESPACE. Quntr vin c th s dng chAUTO hoc MANUAL ch r kiu qun l khng gian mOracle s sdng.

Cp nht li cc global indexes mi khi thc hin t hao tc bo tr parti t ion

Theo mc nh, c thc mt vi phn ca mt bng c phn khu (partitioned tables)

trng thi khng sdng (nh du UNUSABLE) sc np vo trong global indexes. Vta cn xy dng li (rebuild) ton b global index. Oracle9icho php thc hin tng cngvic rebuild ny thng qua mnh UPDATE GLOBAL INDEX c trong cu lnh ALTERTABLE khi thc hin bo tr.

Cho php sdng ng thi nhiu kch c block

Oracle cho php sdng ng thi nhiu kch c blocks (multiple block sizes). Kch thcchun (standard block size) c quy nh trong tham skhi to DB_BLOCK_SIZE nhngcng c th m rng thm 4 gi tr kch thc block phi chun na (nonstandard block

sizes). Cc kch thc blocks phi chun c ch r mi khi to tablespaces. Kch thc blockchun c sdng cho SYSTEM tablespace v hu ht cc tablespaces khc. Vic h tr sdng nhiu kch c block s cho php thc hin trao i cc tablespaces ca cc databasem khng c cng mt kch thc block.

Qun l ng buff er cache

Kch thc ca buffer cache c trong vng nh System Global Area c qun l ng. iuny c ngha l gi tr ca tham sDB_BLOCK_BUFFERS (trong file tham skhi to) c thc thay thbi gi tr c trong tham skhc, tham sDB_CACHE_SIZE. Trong Oracle 9i,buffer cache li c phn chia thnh nhiu bm con (subcaches) nu c sdng ch

multiple block sizes. Bn gi tr kch c block c ch ra trong 4 tham s DB_nK_CACHE_SIZE tng ng .

Qun l ng vng nh SGA

Cc tham skhi to c th tc ng ti kch c ca vng nh SGA. V ta c th thay ikch c ca SGA d dng thng qua cu lnh ALTER SYSTEM SET.

Qun l vic khi phc (undo) tng

Oracle s dng rollback segments lu tr cc thng tin cho khi phc. Vic phc hi(undo) bao gm roll back, undo, v thay i (changes) i vi database mi khi cn. Oracle9i cho php ta to ring mt undo tablespace lu trcc thng tin phc hi ny. Vic s


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dng undo tablespace s lm gim bt tnh phc tp ca vic qun tr vng khng gianrollback segment, v cho php phc hi li cc thng tin di m khng s b trng ln nhau.

Qun l f i les trong Oracle

Mt im mi trong Oracle 9i l qun l files. Thng qua cc tham s khi to

DB_CREATE_FILE_DEST v DB_CREATE_ONLINE_LOG_DEST_ n ta c th ch ra cho hthng cc ng dn c th lu trcc file thuc tablespace, online redo log file hay controlfile. Oracle lun m bo qun l file duy nht trong h thng.

Tng xo cc datafil es

Oracle9i cung cp mt la chn cho php tng xo b (remove) cc datafiles mi khitablespace tng ng b hu thng qua cu lnh DROP TABLESPACE. Tu chn tng ttrong cu lnh ALTER DATABASE TEMPFILE cng c sdng xo cc temporary filetng ng.

Metadata API

Mt PL/SQL package mi, DBMS_METADATA.GET_DDL, c a vo Oracle 9i cho php taly c cc siu dliu (metadata) Cc thng tin tng hp v cc schema object.

Cc bng ngoi - Ext ernal tables

Oracle9icho php ta truy cp theo kiu chc cc d liu trong cc bng ngoi (externaltables). External tables l cc tables m khng nm trong database, v c th cc khundng (format) no . Cu lnh CREATE TABLE ... ORGANIZATION EXTERNAL c

sdng ch ra metadata m t cho external table tng ng. Oracle cung cp iu khintruy cp ORACLE_LOADER, qua cung cp kh nng nh x d liu tng ng vi c phplnh trong control file.

Tng cng cho constraint

Ta sdng mnh USING INDEX trong cu lnh CREATE TABLE hay ALTER TABLE cho php ta ch r index mi khi sdng rng buc unique key hay primary key. Thm vo, ta cng c thngn cn vic hu (dropping).

File tham strn serverOracle lu trcc tham skhi to cho session trong file tham sdi khun dng vn bnv c t ti cc client machine.

Cc tham skhi to ca server nm trong file tham s trn server thng khun dngnh phn v c thc lu trong database.

Temporar y t ablespace mc nh

C th thm vo mnh mi DEFAULT TEMPORARY TABLESPACE vo cu lnh CREATEDATABASE cho php to temporary tablespace ngay trong thi gian to database.Tablespace ny sc sdng nhtemporary tablespace mc nh.


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t t n cho tr ansacti on

Oracle cho php ta gn tn cho mi mt transaction. Tn ca transaction rt c ch cho vicphn bit gim thiu vic nhm ln gia cc transactions.

Mt sthay i t rong Oracle Database Confi gurat ion Assistant

Oracle Database Configuration Assistant c mt sthay i trong thit k. Theo , n cungcp cc mu (templates) gip cho vic tit kim, gim bt vic nh ngha cc object trongdatabase.

Ngi dng cng c thto ra cc mu ny thng qua vic sa i cc mu c sn. Khi todatabase bng cng c Database Configuration Assistant ta cng c ththm vo ngay hocsau cc khun mu gi l cc Oracles new Sample Schemas. Nhng schemas ny lnhng v d ti liu c bn trong Oracle.

Qun l vic sdng index

Ta thm mnh MONITORING USAGE vo trong cu lnh ALTER INDEX c th xcnh v qun l index khi n c thc hin.

Lit k cc phn vng

Oracle 9i gii thiu sdng lit k cc phn vng, n cho php ta ch ra mt danh sch ccgi tr ri rc tng ng vi cc partitioning column ca mi phn vng. Phng thc lit kphn vng (list partitioning method) c a ra nhm mc ch m hnh ho d liu phntn i vi cc gi tr ri rc. Vic ny kh thc hin c bng cc phng php rangepartitioning (phn khu theo khong gi tr) hay hash partitioning (phn khu theo hm bm).

Phn khu t heo hm bm cho cc index-or ganized tables

Oracle 9i cho php sdng phng php bm khi phn khu cc index-organized tables. cc phin bn trc, vic phn khu cho index-organized tables vn thc hin c nhng chbng phng php range method.

Xl cc job queue process linh hot

Cc job queue process c to mt cch linh hot v n ch cn ti shiu ca processesc to thc hin cc jobs ca process ang sn sng cho vic thc hin. Tin trnh

nn (background process) c tn l CJQ sm nhim cng vic ny.

im mi t rong Database Resource Manager

C mt schc nng mi c thm vo Database Resource Manager:

C kh nng to mt active session pool, l ni lu cha c mt s lng ln nhtcc user sessions ng thi ang c thc hin. Nu c nhiu hn slng ln nhtcc sessions cng c thc hin th cc sessions mi ny sc a vo hng i ch thc hin sau. Tuy nhin ta cng c tha ra mt khong thi gian tr(timeout) cho php thc hin hay hu vic thc hin cc sessions mi b sungny.

Tng chuyn users tmt nhm ny sang mt nhm khc tu theo siu chnhca qun tr vin (administrator). Nu mt session c to bi member thuc mtnhm users no thc hin trong khong thi gian di hn thi gian cho php th


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session c thc tng chuyn sang mt nhm khc vi nhng yu cu tinguyn khc.

C kh nng ngn chn thc hin cc thao tc m c dkin l s phi chy trongmt thi gian di hn l khong thi gian cho php.

C kh nng to mt undo pool, l ni cha mt s lng nht nh vng khng giandnh cho vic khi phc thng tin (undo).

C chxc thc v nh xc t hc (Proxy aut hentication and authorization)

Oracle9icho php mt server nm lp gia (middle-tier) xc nhn h mt client. Ta c ththc hin vic ny bng cch a vo mnh GRANT CONNECT THROUGH trong cu lnhALTER USER. Ta cng c thch r vai tr ca lp gia (middle tier) trong vic kt ni ticlient.

Application roles

Oracle cho php gn roles cho cc application users m c kch hot bng cch sdngPL/SQL package. Sdng mnh IDENTIFIED USING package trong cu lnh CREATEROLEthc hin vic ny.


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Chng 2. CC THNH PHN KIN TRC

2.1. KIN TRC ORACLE SERVER

Oracle server l mt h thng qun tr c s d liu i tng-quan h cho php qun lthng tin mt cch ton din. Oracle server bao gm hai thnh phn chnh l Oracle instancev Oracle database.

2.1.1. Oracle Instance

Oracle instance bao gm mt cu trc b nh System Global Area (SGA) v ccbackground processes (tin tr nh nn) c sdng qun tr c s d liu. Oracleinstance c xc nh qua tham smi trng ORACLE_SID ca hiu hnh.

Background

process

Hnh v 1. Kin trc Oracle Server

System Global Area - SGA

SGA l vng b nh chia sc sdng lu trd liu v cc thng tin iu khin caOracle server. SGA c cp pht (allocated) trong b nh ca my tnh m Oracle serverang hot ng trn . Cc User kt ni ti Oracle s chia s cc d liu c trong SGA, vicm rng khng gian b nh cho SGA s lm nng cao hiu sut ca h thng, lu trcnhiu dliu trong h thng hn ng thi gim thiu cc thao tc truy xut a (disk I/O).

SGA bao gm mt vi cu trc b nh chnh:

Shared pool: L mt phn ca SGA lu cc cu trc b nh chia s.

Database buffer cache: Lu trcc d liu c sdng gn nht. Redo log buffer: c sdng cho vic d tm li cc thay i trong c s d liu vc thc hin bi cc background process.

chi tit hn, ta s xem xt c thtng thnh phn.

Share Pool

Shared pool l mt phn trong SGA v c sdng khi thc hin phn tch cu lnh (parsephase). Kch thc ca Shared pool c xc nh bi tham sSHARED_POOL_SIZE ctrong parameter file (file tham s).

Cc thnh phn ca Shared pool gm c: Library cache v Data dictionary cache.


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Hnh v 2. Cu trc Share Pool

Librar y Cache

Library cache lu trthng tin v cc cu lnh SQL c sdng gn nht bao gm:

Ni dung ca cu lnh dng text (vn bn).

Parse tree (cy phn tch) c xy dng tu thuc vo cu lnh. Execution plan (s thc hin lnh) gm cc bc thc hin v ti u lnh.

Do cc thng tin trn c lu trtrong Library cache nn khi thc hin li mt cu lnhtruy vn, trc khi thc hin cu lnh, Server process s ly li cc thng tin c phntch m khng phi phn tch li cu lnh. Do vy, Library cache c thgip nng cao hiusut thc hin lnh.

Data Dictionary Cache

Data dictionary cache l mt thnh phn ca Shared pool lu tr thng tin ca dictionarycache c sdng gn nht nhcc nh ngha cc bng, nh ngha cc ct, usernames,passwords, v cc privileges (quyn).

Trong giai on phn tch lnh (parse phase), Server process s tm cc thng tin trongdictionary cache xc nh cc i tng trong cu lnh SQL v xc nh cc mcquyn tng ng. Trong trng hp cn thit, Server process c th khi to v np ccthng tin tcc file dliu.

Data buff er cache

Khi thc hin mt truy vn, Server process s tm cc blocks cn thit trong database buffercache. Nu khng tm thy block trong database buffer cache, Server process mi c cc

block t data file v to lun mt bn sao ca block vo trong vng nhm (buffercache). Nhvy, vi cc ln truy xut ti block sau ny s khng cn thit phi truy xutvo datafile na.

Hnh v 3. Database buffer cache


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Database buffer cache l vng nh trong SGA sdng lu trcc block d liu c sdng gn nht. Tng t nh kch thc ca blocks d liu c xc nh bi tham sDB_BLOCK_SIZE, kch thc ca vng m trong buffer cache cng c xc nh bitham sDB_BLOCK_BUFFERS.

Oracle server s dng gii thut least recently used (LRU) algorithm lm ti li vngnh. Theo , khi np mi mt block vo bm, trong trng hp bm y, Oracle

server s loi bt block t c sdng nht ra khi bm np block mi vo bm.

Redo log buf fer

Server process ghi li cc thay i ca mt instance vo redo log buffer, y cng l mtphn b nh SGA.

Hnh v 4. Redo log buffer

C mt sc im cn quan tm ca Redo log buffer:

Kch thc c xc nh bi tham sLOG_BUFFER.

Lu trcc redo records (bn ghi hi phc) mi khi c thay i dliu. Redo log buffer c s dng mt cch thng xuyn v cc thay i bi mttransaction c thnm an xen vi cc thay i ca cc transactions khc.

Bm c t chc theo kiu circular buffer (bm ni vng) tc l d liu thayi s tip tc c np ln u sau khi vng m c sdng ht.

Background process

Background process (cc tin trnh nn) thc hin cc chc nng thay cho li gi tin trnhx l tng ng. N iu khin vo ra, cung cp cc c chx l song song nng cao hiu

qu v tin cy. Ty theo tng cu hnh m Oracle instance c cc Background processnh:

Database Writer (DBW0): Ghi li cc thay i trong data buffer cache ra cc file dliu.

Log Writer (LGWR): Ghi li cc thay i c ng k trong redo log buffer vo ccredo log files.

System Monitor (SMON): Kim tra snht qun trong database. Process Monitor (PMON): Dn dp li ti nguyn khi cc tin trnh ca Oracle gp li. Checkpoint Process (CKPT): Cp nht li trng thi ca thng tin trong file iu khin

v file dliu mi khi c thay i trong buffer cache.


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Database Writ er (DBW0)

Server process ghi li cc d liu thay i rollback v d liu ca cc block trong buffer

cache. Database writer (DBWR) ghi cc thng tin c nh du thay i tdatabase buffercache ln cc data files nhm m bo lun c khong trng bm cn thit cho vic sdng.

Hnh v 5. Database Writer (DBWR)

Vi vic sdng ny, hiu sut sdng database sc ci thin do Server processes chto cc thay i trn buffer cache, DBWR ghi dliu vo cc data file cho ti khi:

Slng buffers nh b du t ti gi tr ngng. Tin trnh duyt tt c buffer m vn khng tm thy d liu tng ng. Qu thi gian quy nh.

Log Writ er

Log Writer (LGWR) l mt trong cc background process c trch nhim qun l redo logbuffer ghi li cc thng tin trong Redo log buffer vo Redo log file. Redo log buffer l b m dliu c t chc theo kiu ni vng.


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Hnh v 6. Log Writer (LGWT)LGWR ghi li dliu mt cch tun tvo redo log file theo cc tnh hung sau:

Khi redo log buffer y Khi xy ra timeout (thng thng l 3 giy) Trc khi DBWR ghi li cc blocks b thay i trong data buffer cache vo cc data

files. Khi commit mt transaction.

System Monit or ( SMON)

Tin trnhsystem monitor (SMON) thc hin phc hi cc sc(crash recovery) ngay ti thiim instance c khi ng (startup), nu cn thit. SMON cng c trch nhim dn dpcc temporary segments khng cn c s dng na trong dictionary-managedtablespaces. SMON khi phc li cc transactions b cht mi khi xy ra sc. SMONu nthc hin kim tra v khc phc cc sckhi cn.

Trong mi trng Oracle Parallel Server, SMON process ca mt instance c th thc hinkhi phc instance trong trng hp instance hay CPU ca my tnh gp sc.

Process Monit or ( PMON)

Tin trnh process monitor (PMON) thc hin tin trnh phc hi mi khi c mt user processgp li. PMON c trch nhim dn dp database buffer cache v gii phng ti nguyn muser process s dng. V d, n thit lp li (reset) trng thi ca cc bng ang thchin trong transaction, gii phng cc locks trn bng ny, v hu b process ID ca n rakhi danh sch cc active processes.

PMON kim tra trng thi ca ni gi (dispatcher ) v cc server processes, khi ng li(restarts) mi khi xy ra s c. PMON cng cn thc hin vic ng k cc thng tin vinstance v dispatcher processes vi network listener.

Tng tnhSMON, PMONc gi n mi khi xy ra sctrong h thng.


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Cu trc vt l database

Cu trc vt l bao gm tp hp cc control file, online redo log file v cc datafile:

DatafilesMi mt Oracle database u c thc mt hay nhiu datafiles. Cc database datafiles chaton b d liu trong database. Cc d liu thuc cu trc logic ca database nh tableshay indexes u c lu trdi dng vt l trong cc datafiles ca database.

Mt stnh cht ca datafiles:

Mi datafile ch c thc sdng trong mt database. Bn cnh , datafiles cng cn c mt s tnh cht cho php tng m rng kch

thc mi khi database ht ch lu trd liu. Mt hay nhiu datafiles to nn mt n v lu tr logic ca database gi l

tablespace. Mt datafile ch thuc v mt tablespace.

D liu trong mt datafile c thc ra v lu vo vng nh bm ca Oracle. V d: khimt user mun truy cp d liu trong mt table thuc database. Trong trng hp thng tinyu cu khng c trong cache memory hin thi, n sc c trc tip tcc datafiles rav lu trvo trong b nh.

Tuy nhin, vic b sung hay thm mi d liu vo database khng nht thit phi ghi ngayvo cc datafile. Cc d liu c th tm thi ghi vo b nhgim thiu vic truy xut tib nh ngoi (a) lm tng hiu nng sdng h thng. Cng vic ghi d liu ny cthc hin bi DBWnbackground process.

Redo Log FilesMi Oracle database u c mt tp hp t02 redo log filestr ln. Cc redo log files trongdatabase thng c gi l database's redo log. Mt redo log c to thnh tnhiu redoentries (gi l cc redo records).

Chc nng chnh ca redo log l ghi li tt c cc thay i i vi d liu trong database.Redo log files c sdng bo v database khi nhng hng hc do sc. Oracle chophp sdng cng mt lc nhiu redo log gi l multiplexed redo logcng lu tr ccbn sao ca redo log trn cc a khc nhau.

Cc thng tin trong redo log file chc sdng khi phc li database trong trnghp h thng gp s c v khng cho php vit trc tip d liu trong database ln ccdatafiles trong database. V d: khi c scxy ra nhmt in bt cht chng hn, cc dliu trong b nh khng thghi trc tip ln cc datafiles v gy ra hin tng mt d liu.Tuy nhin, tt c cc d liu b mt ny u c thkhi phc li ngay khi database c mtr li. Vic ny c th thc hin c thng qua vic sdng ngay chnh cc thng tin minht c trong cc redo log files thuc datafiles. Oracle s khi phc li cc database cho nthi im trc khi xy ra sc.

Cng vic khi phc d liu tcc redo log c gi l rolling forward.

Control FilesMi Oracle database u c t nht mt control file. Control file cha cc mc thng tin quy

nh cu trc vt l ca database nh: Tn ca database. Tn v ni lu trcc datafiles hay redo log files.


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Time stamp (mc thi gian) to lp database, ...

Mi khi no mt instance ca Oracle database c m, control file ca n sc sdngxc nh data files v cc redo log files i km. Khi cc thnh phn vt l c database bthay i (v d nh, to mi datafile hay redo log file), Control file sc tng thay itng ng bi Oracle.

Control file cng c sdng n khi thc hin khi phc li dliu.

Cu trc logic databse

Cu trc logic ca Oracle database bao gm cc i tng tablespaces, schema objects,data blocks, extents, v segments.

TablespacesMt database c thc phn chia v mt logic thnh cc n v gi l cc tablespaces,Tablespaces thng bao gm mt nhm cc thnh phn c quan h logic vi nhau.

Databases, Tablespaces, v Datafi lesMi quan h gia cc databases, tablespaces, v datafiles c thc minh ho bi hnh vsau:

Hnh v 8. Quan h gia database, tablespace v datafile

C mt sim ta cn quan tm:

Mi database c thphn chia v mt logic thnh mt hay nhiu tablespace. Mi tablespace c thc to nn, v mt vt l, bi mt hoc nhiu datafiles. Kch thc ca mt tablespace bng tng kch thc ca cc datafiles ca n. V d:

trong hnh v trn SYSTEM tablespace c kch thc l 2 MB cn USERS tablespacec kch thc l 4 MB.

Kch thc ca database cng c thxc nh c bng tng kch thc ca cctablespaces ca n. V d: trong hnh v trn th kch thc ca database l 6 MB.

Schema v Schema ObjectsSchema l tp hp cc i tng (objects) c trong database. Schema objects l cc cutrc logic cho php tham chiu trc tip ti d liu trong database. Schema objects baogm cc cu trc nh tables, views, sequences, stored procedures, synonyms, indexes,clusters, v database links.


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Data Blocks, Ext ents, and Segment sOracle iu khin khng gian lu trtrn a cng theo cc cu trc logic bao gm cc datablocks, extents, v segments.

Oracle Data BlocksL mc phn cp logic thp nht, cc d liu ca Oracle database c lu tr trong ccdata blocks. Mt data block tng ng vi mt s lng nht nh cc bytes vt l cadatabase trong khng gian a cng. Kch thc ca mt data blockc ch ra cho miOracle database ngay khi database c to lp. Database sdng, cp pht v gii phngvng khng gian lu trthng qua cc Oracle data blocks.

Extents

L mc phn chia cao hn v mt logic cc vng khng gian trong database. Mt extentbaogm mt s data blocks lin tip nhau, cng c lu tr ti mt thit b lu gi. Extent

c sdng lu trcc thng tin c cng kiu.

Segments

L mc phn chia cao hn na v mt logic cc vng khng gian trong database. Mtsegment l mt tp hp cc extents c cp pht cho mt cu trc logic . Segment c thc phn chia theo nhiu loi khc nhau:

Datasegment

Mi mt non-clustered table c mt data segment. Cc d liu trong mttable c lu tr trong cc extents thuc data segment . Vi mtpartitioned table th mi each partition li tng ng vi mt datasegment.Mi Cluster tng ng vi mt data segment. D liu ca tt c cc tabletrong cluster u c lu trtrong data segment thuc Cluster .

indexsegment

Mi mt index u c mt index segment lu trcc d liu ca n. Trongpartitioned index th mi partition cng li tng ng vi mt indexsegment.

rollbacksegment

Mt hoc nhiu rollback segments ca database c to lp bi ngiqun tr database lu tr cc d liu trung gian phc v cho vic khiphc d liu.

Cc thng tin trong Rollback segment c sdng : To sng nht cc thng tin c c tdatabase Sdng trong qu trnh khi phc d liu Phc hi li cc giao dch cha commit i vi mi user

temporarysegment

Temporary segments c tng to bi Oracle mi khi mt cu lnhSQL statement cn n mt vng nh trung gian thc hin cc cngvic ca mnh nh sp xp d liu. Khi kt thc cu lnh , cc extentthuc temporary segment s li c hon tr cho h thng.

Oracle thc hin cp pht vng khng gian lu trmt cch linh hot mi khi cc extentscp pht sdng ht.


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Cc cu trc vt l khc

Ngoi ra, Oracle Server cn sdng cc file khc lu trthng tin. Cc file bao gm:

Parameter file: Parameter file ch ra cc tham sc sdng trong database. Ngiqun tr database c th sa i mt vi thng tin c trong file ny. Cc tham strong parameter file c vit dng vn bn.

Password file: Xc nh quyn ca tng user trong database. Cho php ngi sdngkhi ng v tt mt Oracle instance. Archived redo log files: L bn off line ca cc redo log files cha cc thng tin cn

thit phc hi dliu.

2.1.3. Qun tr c s d liu Oracle

Qun tr c s d liu l cng vic bo tr v vn hnh Oracle server n c th tip nhnv x l c tt c cc yu cu (requests) t pha Client. lm c iu ny, ngiqun tr vin c s dliu cn phi hiu c kin trc ca Oracle database.

2.1.4. Thit lp cc tham s khi to nh hng ti kch c b nh SGA

Tham skhi to nh hng ti kch thc b nh cp pht cho vng System Global Area.Ngoi tr tham sSGA_MAX_SIZE, cn li cc tham skhc u l tham sng tc l cth thay i gi tr ca chng ngay trong lc database ang chy thng qua cu lnh ALTERSYSTEM. Kch thc ca SGA cng c ththay i c trong qu trnh chy database.

Thit lp tham scho Buff er Cache

Tham skhi to buffer cache quy nh kch thc ca buffer cache l mt phn ca SGA. .

Ta sdng cc tham sDB_CACHE_SIZE v mt trong nhng tham sDB_nK_CACHE_SIZE cho php sdng ch multiple block sizes i vi database. Oracle s tng gncc gi tr mc nh cho tham s the DB_CACHE_SIZE, cn tham sDB_nK_CACHE_SIZE sc gn mc nh bng 0.

Kch thc ca buffer cache s c nh hng nhiu ti hiu sut thc hin ca h thng.Kch thc cng ln th cng gim bt vic c v ghi a. Tuy nhin, kch thc ca cacheln s tn nhiu b nh v s c nhiu tn km trong vic thc hin paging (phn trang)hay swapping (trao i) b nh.

Tham sDB_CACHE_SI ZE

Tham s khi to DB_CACHE_SIZEc sdng thay th cho tham sDB_BLOCK_BUFFERSca cc phin bn Oracle trc kia. Tham sDB_CACHE_SIZE quy nh kch thc ca blockbuffers chun. Kch thc ca mt block chun li c quy nh trong tham sDB_BLOCK_SIZE.

Tuy vy, tham sDB_BLOCK_BUFFERS vn c sdng tng thch vi cc phin bntrc, tuy nhin gi tr ca n khng c sdng cho cc tham sng.

Tham sDB_nK_CACHE_SI ZE

Ch ra kch c l bi snguyn ln kch thc ca block buffers. N c ch ra bi cc thams:

DB_2K_CACHE_SIZE


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DB_4K_CACHE_SIZE

DB_8K_CACHE_SIZE

DB_16K_CACHE_SIZE

DB_32K_CACHE_SIZE.

Mi tham sch ra kch c ca buffer cache tng ng vi kch c ca block.V d:

DB_BLOCK_SIZE=4096

DB_CACHE_SIZE=12M

DB_2K_CACHE_SIZE=8M

DB_8K_CACHE_SIZE=4M

v d ny, cc tham sch ra kch thc block chun ca database l 4K. Kch thc cachetng ng vi kch thc block chun l 12M. Cc kch thc m rng ca cache l 2K v 8Ksc t li vi gi tr tng ng l 8M v 4M.

iu chnh k ch c ca Shar ed Pool

Tham sSHARED_POOL_SIZE trong phin bn Oracle 9i l tham sng, tc l c th thayi c gi tr ca n (iu ny khng th thc hin c trong cc phin bn trc). Ncho php ta thay i kch thc ca shared pool l mt trong cc thnh phn ca SGA. Theomc nh Oracle cng chn mt gi tr mc nh ph hp cho tham sny.

iu chnh k ch c ca Large Pool

Tng tnhSHARED_POOL_SIZE, tham sLARGE_POOL_SIZE cng l mt tham sng,

n cho php ta iu chnh kch c ca large pool, y cng l mt thnh phn trong SGA. .

Gii hn kch c ca SGA

Tham sSGA_MAX_SIZE quy nh kch c ln nht ca System Global Area . Ta cng c ththay i kch c ca buffer caches, shared pool v large pool, tuy nhin vic thay i nynn l m rng gi tr kch thc cho cc thnh phn ca SGA. Gi tr m rng thm nycng khng nn t ti ngng ca SGA_MAX_SIZE.

Trong trng hp ta khng ch r gi tr ca SGA_MAX_SIZE th Oracle s tng gn gi trny bng tng skch c ca cc thnh phn ca SGA lc ban u.

2.2.KT NI TI ORACLE SERVER

2.2.1. M hnh kt ni

Cc Client c thkt ni ti Oracle Server thng qua 03 cch sau:

Kt ni trc tip: kt ni m Client nm trn cng mt my ch Oracle server. Kt ni hai lp (two-tiered) client-server: Client nm trn mt my tnh khc v kt

ni trc tip ti my ch Oracle Server. Kt ni ba lp (three-tiered): Client nm trn my tnh khc vi my ch Oracle

Server, n giao tip vi mt ng dng hay mt my ch mng (network server) viu khin ng dng hay my ch ny kt ni ti Oracle server.


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Hnh v 9. Kt ni ti Oracle server2.2.2. Mt s khi nim c bn lin quan n kt ni

Connection (lin kt)

Lin kt l ng lin lc gia mt user process v mt Oracle server. Trong trng hpuser sdng cc tool hoc cc ng dng ngay trn cng mt my vi Oracle server, nglin lc sc to lp ngay trn my . Trong trng hp user nm trn mt my khcth lin kt s sdng ng mng kt ni ti Oracle server.

Session (phin)

Mt phin tng ng vi mt lin kt c thca mt user ti mt Oracle server. Phin btu khi user kt ni ti Oracle Server c kim tra hp l v kt thc khi user thc hinlog out khi Oracle Server hoc user kt thc mt cch bt thng. Mt user cng mt lcc thc nhiu phin lm vic kt ni ti Oracle Server thng qua cc ng dng hay cctool khc nhau. V du: User c th ng thi c cc phin lm vic gia SQL*Plus,Developer/2000 Form,... ti Oracle Server.

Lu : Phin ch to lp c khi Oracle Server sn sng cho vic kt ni ca cc client.

2.2.3. Kt ni ti database

Cc bc thc hin kt ni

kt ni ti database trc tin, cn phi to lin kt ti Oracle Server. Lin kt ti OracleServer c to theo cc bc sau:

User s dng cng c SQL*Plus hay s dng cc cng c khc ca Oracle nhDeveloper/2000 Forms khi to tin trnh. Trong m hnh Client-Server, cc cngc hay ng dng ny c chy trn my Client.

User thc hin log in vo Oracle server vi vic khai bo username, password v tnlin kt ti database. Cc ng dng tools s to mt tin trnh kt ni ti Oracleserver qua cc tham sny. Tin trnh ny c gi l tin trnh phc v. Tin trnhphc v s giao tip vi Oracle server thay cho tin trnh ca user chy trn myClient.


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V d thc hin kt ni ti database

hiu r hn v cc bc thc hin kt ni, ta hy xem xt mt v d m t vic kt niti Oracle database thc hin bi mt user ti mt my tnh khc c kt ni ti my tnh mOracle server ang chy trn . Vic kt ni c thc hin thng qua ng mng bngcch sdng dch v Oracle Net8.

1. Ti my ch, cn m bo Oracle server ang chy v sn sng n nhn cc tnhiu tpha Client. My ch ny c gi l hosthay database server.

2. Ti mt my trm c chy cc ng dng (gi l local machinehay client workstation)s thc hin cc user process kt ni ti database. Client application thc hinthit lp mt kt ni ti server thng qua Net8 driver.

3. My ch server trn c cc Net8 driver. Server s thc hin vic nghe v d tmtt c cc yu cu gi n tpha client v sau s to mt server process tngng vi user process.

4. Khi user thc hin mt cu lnh SQL hay commit mt transaction. V d nhuser dliu trn mt dng trong mt table.

5. Server process s nhn v cu lnh gi ti tClient, kim tra v phn tch cu lnh,vic ny c thc hin trong shared pool. Tip theo , Server process s kim traquyn truy nhp dliu ca user.

6. Server process tr v cc gi tr d liu yu cu tcc dliu c trong datafile haytrong system global area.

7. Server process thay i cc d liu c trong system global area. DBWnprocess ghi licc blocks thay i ra a. LGWR process s ghi li ngay lp tc cc bn ghithay i vo online redo log file ngay khi transaction c commit.

8. Trong trng hp transaction thc hin thnh cng, server process s gi thng bohon tt qua ng mng ti Client. Ngc li, s c mt error message gi tiClient.


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Chng 3. CC CNG C QUN TR ORACLE

3.1.CC CNG CQUN TRCSDLIU ORACLE

Oracle hin ti cung cp rt nhiu cng c cho php qun tr c s d liu. C thkrasau y mt scng c c bn sau:

Cng c Din gii

Server Manager LineMode

Cng c qun tr c s d liu Oracle theo ch dng lnh nhstart (khi ng), shutdown (dng) database,...

SQL*Plus Line Mode y l mt tin ch sdng cho vic cng qun tr nh startingup, shutting down, hoc phc hi database.

Oracle EnterpriseManager

L cng c c giao din ha thc hin vic qun tr, iukhin v thay i mt hoc nhiu database.

SQL*Loader Tin ch s dng np cc file bn ngoi vo trong cc bng

ca Oracle .Cng c Export vImport

Tin ch sdng exporting hoc importing d liu theo khundng ca Oracle.

Password File Tin ch sdng to file mt khu trong database.

thun tin, ti liu s trnh by hai cng c thng dng nht qun tr c s d liul:

Server Manager Line Mode Oracle Enterprise Manager

3.2.SERVER MANAGER LINE MODE

3.2.1. Truy nhp Server Manager Line Mode

User (ngi sdng) c thvo Server Manager Line Mode theo hai cch:

C:\svrmgrl

Cch ny ch vo Server Manager Line Mode m cha thc hin kt ni c thti database

Lu : trong cc phin bn c, ta g svrmgrl30 thay v svrmgrl

Hoc:

C:\svgrmrl command=connect internal/admin

C:\svgrmrl command=@c:\example.sql

Vo Server Manager Line Mode ng thi thc hin lnh lun.

K tsdng t rong Server Manager Line Mode

Vi Server Manager Line Mode, ta c th thc hin cu lnh SQL hoc on lnh PL/SQL.Cc cu lnh c kt thc bi k tchm phy ;

Sdng k t /kt thc cu lnh trong trng hp bm phm Enter xung dng.

Ngoi ra, ta c thchy file script cha cc cu lnh SQL v PL/SQL. Bng cch sdng kt @ trc tn file script.


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3.2.2. Phn nhm cc lnh trong Server manager

Loi lnh Tn lnh

Lnh khng cn ktni ti database

EXIT

REMARK

SET

SHOWSPOOL

Cc lnh cn nmc quyn truynhp

CONNECT/DISCONNECT

DESCRIBE

EXECUTE

SHOW ERRORS

SHOW PARAMETER

SHOW SGA

Cc lnh cn nmc quyn truynhp c bit

CONNECT AS SYSDBA

CONNECT AS SYSOPERARCHIVE LOG

RECOVER DATABASE

STARTUP/SHUTDOWN

3.2.3. Din gii cc lnh trong Server manager

Tn lnh Din gii

EXIT ng SQL Worksheet, thot khi Server Manager

REMARK Thm vo li ch dn, thng hay sdng trong file SQL scriptSET Thit lp hoc thay i cc tnh cht c trong phin lm vic hin

thi.

SHOW Hin th cc thit t hin thi

SPOOL Cho php hoc thi cho php chuyn hng kt xut dliu ra file

CONNECT/

DISCONNECT

Kt ni hoc hu kt ni ti database

DESCRIBE Xem cu trc ca mt function, package, package body, procedure,table, object, view

EXECUTE Thc hin mt dng lnh PL/SQL

SHOW ERRORS Hin th cc li pht sinh ca th tc, hm hay package

SHOW PARAMETER Hin th gi tr hin thi ca mt hay nhiu tham s khi to

SHOW SGA Hin th thng tin v SGA ca Instance hin thi

CONNECT/AS

SYSDBA

Kt ni ti database vi c quyn qun tr

ARCHIVE LOG Khi ng v dng vic lu tr tng i vi cc file online redolog files, redo log file

RECOVER

DATABASE

Phc hi li mt hay nhiu tablespaces


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STARTUP/

SHUTDOWN

Khi ng hoc tt Oracle instance

3.3.ORACLE ENTERPRISE MANAGER

Oracle Enterprise Manager (OME) l phng tin cho php c c ci nhn tng thv tonb h thng. Trong c cy phn cp v cc hnh nh ha v cc i tng v quan hgia chng trong h thng.

OME c cc tin trnh Intelligent Agent processes cho php qun l txa cc dch v chung- common services nhjobs, events, mt cch d dng.

OME cng bao gm c nhng ng dng qun l chuyn bit: DBA Management Pack,Advanced Management Packs.

Bn cnh , OME cn cung cp mt lng ln cc hm API cho php tch hp vi cc hthng qun l ng dng khc. Bao gm c cc h thng qun l ca Oracle v khng phica Oracle.

OEM Console c trong c Windows NT v Windows 95.

Hnh v 10.Oracle Enterprise Manager

3.3.1. Kin trc OME

Kin trc OME l m rng ca kin trc Client/Server, n c kin trc ba lp. Lp thnht cha cc Java-based console v cc ng dng tch hp cho php ci t

v chy bi cc Web browser. Lp thhai l Oracle Management Server - OMS. Chc nng chnh ca OMS l x l

v qun tr tt c cc tc v ca h thng, tp trung qun l v phn phi iu khingia cc clients v cc nt iu khin - managed nodes. OEM s dng OracleEnterprise Manager repository duy tr d liu h thng, d liu ng dng v cctrng thi ca cc thc thiu khin phn tn trong h thng, cho php ngi dngc thtruy cp v chia s cc vng dliu lu tr.

Lp thba bao gm cc ch nhdatabases, nodes v cc dch v qun l khc.


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3.3.2. Cc dch v chung

OEM c cc dch v cho php qun l cc nodes trn mng (network)

Dch v pht hin - Discovery service: OEM tng pht hin (nh v) tt c ccdatabase v cc dch v chy trn cc nodes, mt khi cc nodes c xc nh. Ccdch v ny bao gm Web servers, listeners, machines, parallel servers, video servers,v cc services khc.

Job Scheduling System: cho php thc hin tng lp li cc tc v. H thng chophp to v qun l cc jobs, ln khoch thc hin chng v cho php xem, chia sthng tin xc nh Jobs.

Event Management System: cho php qun l mi trng mng (networkenvironment) x l cc trng hp mt dch v, thiu hoc ht vng lu tr, v ccvn khc nhsdng ti nguyn CPU. Mi khi cc events c pht hin, ngiqun tr c ththng bo hoc sa n.

Bo mt - Security: cc tham s bo mt xc nh cho tng dch v (services), itng (objects), v tng user qun tr (administrators).

Dch v kho lu trchia s (Shared Repository)

OEM l mt h thng a ngi dng - multiuser system. Mi qun tr vin c mt accountring ng nhp vo h thng. Ty theo vic thit t quyn hn, m qun tr vin cth truy cp vo cc d liu lu trong kho trung tm, kho c chia s cho tt c cc quntr vin ca OEM thc hin cng vic qun l.

3.3.3. Oracle Configuration Assistant

Configuration Assistant l cng c cho php to cc shared repositories, t li cu hnh chodatabase v thit t cu hnh cho cc local console (n v iu khin cc b).Configuration Assistant c tng khi ng ngay sau khi hon tt qu trnh ci t ca

Universal Installer. Ta cng c thkhi ng ng dng ny bng tay (chy lnh %emrepmgrtdu nhc h thng).

3.3.4. Oracle Enterprise Manager Console

Bao gm c cy phn cp v hnh nh ha biu din cc i tng trong h thng.

1. Cc nt c biu tng: cho php gi cc ng dng khc cng thc hin vicqun tr cc tc v (task). Vic ny cng c ththc hin thng qua mc chn tngng trn menu.

2. Navigator hay object explorer:c t chc di dng cy phn cp. N cho

php xem cc Oracle services trong mng lm vic. Navigator cho php qun tr vinc thbrowse cc Oracle services, nhdatabases, listeners, nodes, v name servers,qua c thsa i cc tnh cht ca cc i tng; v d: ngi dng c ththayi ni dung ca bng.

3. Job system: cho php thc hin cc tc v txa lin quan ti listeners, databases.Job system da trn cc th tc trong Tool Control Language (TCL) engine.


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Hnh v 11.Oracle Enterprise Manager

4. Menu cho php khi to cc ng dng qun tr khc v thc hin nhiu tc v khcnhau.

5. Map hay topographical view cho php cc Oracle services c thc gp li tytheo quan h v khng gian, chc nng, hay c hai. Map view cho php ngi sdng tp trung vo cc i tng cn qun l.

6. Event system iu khin v thng bo cc trng thi ca h thng.

3.4.CC CNG CQUN TRKHC

Ngoi hai cng c chnh nh ktrn, Oracle cn h tr b cc cng c chun khc nh:

I nstance Manager: dng iu khin database nh ngha v khi to cc thamslin quan ti cc tnh cht ca instance.

Schema Manager: dng to lp v qun l cc i tng nhtables, indexes, vviews.

Securi t y Manager: dng qun l cc users v phn quyn cho cc users ny Storage Manager: dng t chc cc database files v qun l cc rollback

segments. SQL Worksheet : giao tip theo kiu dng lnh, n cho php thc hin cc cu lnh

SQL v PL/SQL cng nhl cc cu lnh ca Server Manager Backup Manager: dng sao lu, phc hi v bo tr databases, qun l cc redo

log files. Data Manager: dng np v t chc

giao trinh oracle9i

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