Expert PL/SQL practices for Oracle developers and DBAs 9781430234852, 1430234857

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%XPERT0,31,0RACTICES FOR/RACLE$EVELOPERSAND$"!S







■■■ *OHN"ERESNIEWICZ !DRIAN"ILLINGTON -ARTIN"àCHI -ELANIE#AFFREY 2ON#RISCO ,EWIS#UNNINGHAM $OMINIC$ELMOLINO 3UE(ARPER 4ORBEN(OLM #ONNOR-C$ONALD !RUP.ANDA 3TEPHAN0ETIT -ICHAEL2OSENBLUM 2OBYN3ANDS 2IYAJ3HAMSUDEEN



%XPERT0,31,0RACTICESFOR/RACLE$EVELOPERSAND$"!S #OPYRIGHTÚBY*OHN"ERESNIEWICZ !DRIAN"ILLINGTON -ARTIN"ÓCHI -ELANIE#AFFREY 2ON#RISCO ,EWIS#UNNINGHAM $OMINIC$ELMOLINO 3UE(ARPER 4ORBEN(OLM #ONNOR-C$ONALD !RUP.ANDA 3TEPHAN0ETIT -ICHAEL2OSENBLUM 2OBYN3ANDS 2IYAJ3HAMSUDEEN !LLRIGHTSRESERVED.OPARTOFTHISWORKMAYBEREPRODUCEDORTRANSMITTEDINANYFORMORBYANYMEANS ELECTRONICORMECHANICAL INCLUDINGPHOTOCOPYING RECORDING ORBYANYINFORMATIONSTORAGEORRETRIEVAL SYSTEM WITHOUTTHEPRIORWRITTENPERMISSIONOFTHECOPYRIGHTOWNERANDTHEPUBLISHER )3".     )3".     (eBook) 4RADEMARKEDNAMES LOGOS ANDIMAGESMAYAPPEARINTHISBOOK2ATHERTHANUSEATRADEMARKSYMBOL WITHEVERYOCCURRENCEOFATRADEMARKEDNAME LOGO ORIMAGEWEUSETHENAMES LOGOS ANDIMAGESONLY INANEDITORIALFASHIONANDTOTHEBENEFITOFTHETRADEMARKOWNER WITHNOINTENTIONOFINFRINGEMENTOF THETRADEMARK 4HEUSEINTHISPUBLICATIONOFTRADENAMES TRADEMARKS SERVICEMARKS ANDSIMILARTERMS EVENIFTHEYARE NOTIDENTIFIEDASSUCH ISNOTTOBETAKENASANEXPRESSIONOFOPINIONASTOWHETHERORNOTTHEYARESUBJECT TOPROPRIETARYRIGHTS 0RESIDENTAND0UBLISHER0AUL-ANNING ,EAD%DITOR*ONATHAN'ENNICK 4ECHNICAL2EVIEWERS#HRIS"ECK -IKE'ANGLER 4OON+OPPELAARS %DITORIAL"OARD3TEVE!NGLIN -ARK"ECKNER %WAN"UCKINGHAM 'ARY#ORNELL *ONATHAN'ENNICK *ONATHAN(ASSELL -ICHELLE,OWMAN *AMES-ARKHAM -ATTHEW-OODIE *EFF/LSON *EFFREY 0EPPER &RANK0OHLMANN $OUGLAS0UNDICK "EN2ENOW #LARKE $OMINIC3HAKESHAFT -ATT 7ADE 4OM7ELSH #OORDINATING%DITOR#ORBIN#OLLINS #OPY%DITOR-ARY"EHR 0RODUCTION3UPPORT0ATRICK#UNNINGHAM )NDEXER30)'LOBAL !RTIST!PRIL-ILNE #OVER$ESIGNER!NNA)SHCHENKO $ISTRIBUTEDTOTHEBOOKTRADEWORLDWIDEBY3PRINGER3CIENCE"USINESS-EDIA ,,# 3PRING3TREET TH&LOOR .EW9ORK .90HONE  302).'%2 FAX   E MAIL ^aSTab]h/b_aX]VTabQ\R^\ ORVISITfffb_aX]VTa^][X]TR^\ &ORINFORMATIONONTRANSLATIONS PLEASEE MAILaXVWcb/P_aTbbR^\ ORVISITfffP_aTbbR^\ !PRESSANDFRIENDSOF%$BOOKSMAYBEPURCHASEDINBULKFORACADEMIC CORPORATE ORPROMOTIONALUSE E"OOKVERSIONSANDLICENSESAREALSOAVAILABLEFORMOSTTITLES&ORMOREINFORMATION REFERENCEOUR 3PECIAL"ULK3ALESnE"OOK,ICENSINGWEBPAGEATfffP_aTbbR^\Qd[ZbP[Tb 4HEINFORMATIONINTHISBOOKISDISTRIBUTEDONANhASISvBASIS WITHOUTWARRANTY!LTHOUGHEVERY PRECAUTIONHASBEENTAKENINTHEPREPARATIONOFTHISWORK NEITHERTHEAUTHORS NOR!PRESSSHALLHAVE ANYLIABILITYTOANYPERSONORENTITYWITHRESPECTTOANYLOSSORDAMAGECAUSEDORALLEGEDTOBECAUSED DIRECTLYORINDIRECTLYBYTHEINFORMATIONCONTAINEDINTHISWORK



Contents at a Glance !BOUTTHE!UTHORSXVII !BOUTTHE4ECHNICAL2EVIEWERSXX )NTRODUCTIONXXI ■#HAPTER$O.OT5SE ■#HAPTER$YNAMIC31,(ANDLINGTHE5NKNOWN ■#HAPTER0,31,AND0ARALLEL0ROCESSING ■#HAPTER7ARNINGSAND#ONDITIONAL#OMPILATION ■#HAPTER0,31,5NIT4ESTING ■#HAPTER"ULK31,/PERATIONS ■#HAPTER+NOW9OUR#ODE ■#HAPTER#ONTRACT /RIENTED0ROGRAMMING ■#HAPTER0,31,FROM31, ■#HAPTER#HOOSINGTHE2IGHT#URSOR ■#HAPTER0,31,0ROGRAMMINGINTHE,ARGE ■#HAPTER%VOLUTIONARY$ATA-ODELING ■#HAPTER0ROFILINGFOR0ERFORMANCE ■#HAPTER#ODING#ONVENTIONSAND%RROR(ANDLING ■#HAPTER$EPENDENCIESAND)NVALIDATIONS )NDEX

III



Contents !BOUTTHE!UTHORSXVII !BOUTTHE4ECHNICAL2EVIEWERSXX )NTRODUCTIONXXI ■#HAPTER$O.OT5SE 2OW BY 2OW0ROCESSING .ESTED2OW BY 2OW0ROCESSING ,OOKUP1UERIES %XCESSIVE!CCESSTO$5!, !RITHMETICSWITH$ATE !CCESSTO3EQUENCES 0OPULATING-ASTER $ETAIL2OWS

%XCESSIVE&UNCTION#ALLS 5NNECESSARY&UNCTION%XECUTION #OSTLY&UNCTION#ALLS

$ATABASE,INK#ALLS %XCESSIVE5SEOF4RIGGERS %XCESSIVE#OMMITS %XCESSIVE0ARSING 3UMMARY

IV

■ #/.4%.43

■#HAPTER$YNAMIC31,(ANDLINGTHE5NKNOWN 4HE(ERO .ATIVE$YNAMIC31, $YNAMIC#URSORS $"-3?31,

3AMPLEOF$YNAMIC4HINKING 3ECURITY)SSUES 0ERFORMANCEAND2ESOURCE5TILIZATION !NTI 0ATTERNS #OMPARING)MPLEMENTATIONSOF$YNAMIC31,

/BJECT$EPENDENCIES .EGATIVE%FFECTS 0OSITIVE%FFECTS

3UMMARY ■#HAPTER0,31,AND0ARALLEL0ROCESSING 7HY0ARALLEL0ROCESSING ,AWS!FFECTING0ARALLEL0ROCESSING 4HE2ISEOF"IG$ATA 0ARALLELVS$ISTRIBUTED0ROCESSING 0ARALLEL(ARDWARE!RCHITECTURES )DENTIFY9OUR'OALS 3PEEDUP 3CALING5P $EGREEOF0ARALLELISM

#ANDIDATE7ORKLOADSFOR0ARALLEL0ROCESSING 0ARALLELISMAND/,40 0ARALLELISMAND.ON /,407ORKLOADS

V

■ #/.4%.43

4HE-AP2EDUCE0ROGRAMMING-ODEL "EFORE,OOKINGTO0,31, 0ROCESSES!VAILABLEFOR0ARALLEL!CTIVITIES 5SING0ARALLEL%XECUTION3ERVERSFOR-AP2EDUCE 0IPELINED4ABLE&UNCTIONS 'UIDANCE 0ARALLEL0IPELINED4ABLE&UNCTIONS3UMMARY

3UMMARY ■#HAPTER7ARNINGSAND#ONDITIONAL#OMPILATION 0,31,7ARNINGS "ASICS 5SING7ARNINGS 0ROMOTING7ARNINGSTO%RRORS )GNORING7ARNINGS #OMPILATIONAND7ARNINGS &INAL7ORDSON7ARNINGS

#ONDITIONAL#OMPILATION "ASICS 7HAT0ARTOFTHE#ODEIS2UNNING "ENEFITSOF0REPROCESSING#ODE )NVALIDATIONS #ONTROLLING#OMPILATION )NQUIRY6ARIABLES &INAL7ORDSON#ONDITIONAL#OMPILATION

3UMMARY

VI

■ #/.4%.43

■#HAPTER0,31,5NIT4ESTING 7HY4EST9OUR#ODE 7HAT)S5NIT4ESTING $EBUGGINGOR4ESTING 7HEN3HOULD9OU"UILD4ESTS

4OOLSFOR"UILDING5NIT4ESTS UT0,31,7ORKINGWITH#OMMAND,INE#ODE 1UEST#ODE4ESTERFOR/RACLE /RACLE31,$EVELOPER

0REPARINGAND-AINTAININGTHE5NIT4EST%NVIRONMENT #REATINGTHE5NIT4EST2EPOSITORY -AINTAININGTHE5NIT4EST2EPOSITORY )MPORTING4ESTS

"UILDING5NIT4ESTS 5SINGTHE5NIT4EST7IZARD #REATINGTHE&IRST)MPLEMENTATION !DDING3TARTUPAND4EARDOWN0ROCESSES #OLLECTING#ODE#OVERAGE3TATISTICS 3PECIFYING0ARAMETERS !DDING0ROCESS6ALIDATION 3AVING4ESTS $EBUGGINGAND2UNNING4ESTS

"ROADENINGTHE3COPEOFTHE4ESTS #REATING,OOKUP6ALUES 3EEDING4EST)MPLEMENTATIONS #REATINGA$YNAMIC1UERY

VII

■ #/.4%.43

3UPPORTING5NIT4EST&EATURES 2UNNING2EPORTS #REATINGA,IBRARYOF#OMPONENTS %XPORTING )MPORTING AND3YNCHRONIZING4ESTS "UILDING3UITES

2UNNING4ESTSFROMTHE#OMMAND,INE 3UMMARY ■#HAPTER"ULK31,/PERATIONS 4HE(ARDWARE3TORE 3ETTINGFORTHE%XAMPLESINTHIS#HAPTER "ULK/PERATIONSIN0,31, 'ETTING3TARTEDWITH"5,+&ETCH 4HREE#OLLECTION 3TYLE$ATATYPES 7HYSHOULD)BOTHER -ONITORING"ULK#OLLECT/VERHEADS 2EFACTORING#ODETO5SE"ULK#OLLECT

"ULK"INDING 'ETTING3TARTEDWITH"ULK"IND -EASURING"ULK"INDING0ERFORMANCE -ONITORING-EMORY5SAGE )MPROVEMENTSING

%RROR(ANDLINGWITH"ULK"IND 3!6%%8#%04)/.3WITH"ATCHES ,/'%22/23#LAUSE 2OBUST"ULK"IND

!*USTIFICATIONFOR-ASSIVE#OLLECTIONS 4HE2EAL"ENEFIT#LIENT"ULK0ROCESSING 3UMMARY

VIII

■ #/.4%.43

■#HAPTER+NOW9OUR#ODE 7HAT4HIS#HAPTER7ILLAND7ILL.OT #OVER !UTOMATED#ODE!NALYSIS 3TATIC!NALYSIS $YNAMIC!NALYSIS

7HENTO!NALYZE 0ERFORMING3TATIC!NALYSIS 4HE$ATA$ICTIONARY 0,3#/0%

0ERFORMING$YNAMIC!NALYSIS $"-3?02/&),%2AND$"-3?42!#% $"-3?(02/&

3UMMARY ■#HAPTER#ONTRACT /RIENTED0ROGRAMMING $ESIGNBY#ONTRACT 3OFTWARE#ONTRACTS "ASIC#ONTRACT%LEMENTS !SSERTIONS 2EFERENCES

)MPLEMENTING0,31,#ONTRACTS "ASIC!33%240ROCEDURE 3TANDARD0ACKAGE ,OCAL!33%24 %NFORCING#ONTRACTS5SING!33%24 !N!DDITIONAL)MPROVEMENT #ONTRACT /RIENTED&UNCTION0ROTOTYPE

%XAMPLE4ESTING/DDAND%VEN)NTEGERS

IX

■ #/.4%.43

5SEFUL#ONTRACT0ATTERNS .OT .5,,)..OT .5,,/54 &5.#4)/.2%452..OT .5,, &5.#4)/.2%452."//,%!..OT .5,, #HECK&UNCTIONS2%452.425%/2!33%24&!),

0RINCIPLES&OR"UG &REE#ODE !SSERT0RECONDITIONS2IGOROUSLY -ODULARIZE2UTHLESSLY !DOPT&UNCTION "ASED)NTERFACES #RASHON!33%24&!), 2EGRESSION4EST9OUR0OSTCONDITIONS !VOID#ORRECTNESS 0ERFORMANCE4RADEOFFS /RACLEG/PTIMIZED#OMPILATION

3UMMARY ■#HAPTER0,31,FROM31, 4HE#OSTOF5SING0,31,&UNCTIONSIN31, #ONTEXT 3WITCHING %XECUTIONS 3UBOPTIMAL$ATA!CCESS /PTIMIZER$IFFICULTIES 4HE2EAD #ONSISTENCY4RAP /THER)SSUES

2EDUCINGTHE#OSTOF0,31,&UNCTIONS !3ENSEOF0ERSPECTIVE 5SING31,!LTERNATIVES 2EDUCING%XECUTIONS

X

■ #/.4%.43

!SSISTINGTHE#"/ 4UNING0,31,

3UMMARY ■#HAPTER#HOOSINGTHE2IGHT#URSOR %XPLICIT#URSORS 4HE!NATOMYOFAN%XPLICIT#URSOR %XPLICIT#URSORSAND"ULK0ROCESSING 2%&#URSORSIN"RIEF

)MPLICIT#URSORS 4HE!NATOMYOFAN)MPLICIT#URSOR 4HE)MPLICIT#URSORANDTHE%XTRA&ETCH4HEORY

3TATIC2%&#URSORS #URSOR6ARIABLE2ESTRICTIONS,AUNDRY,IST 9OUR#LIENTAND2%&#URSORS !&EW7ORDSABOUT0ARSING

$YNAMIC2%&#URSORS %XAMPLEAND"EST5SE 4HE4HREATOF31,)NJECTION $ESCRIBING2%&#URSOR#OLUMNS

3UMMARY ■#HAPTER0,31,0ROGRAMMINGINTHE,ARGE 4HE$ATABASEAS0,31, "ASED!PPLICATION3ERVER #ASE3TUDY4HE!VALOQ"ANKING3YSTEM 3TRENGTHSOF"USINESS,OGICINTHE$ATABASEWITH0,31, ,IMITSOFTHE$ATABASEAS0,31, "ASED!PPLICATION3ERVER 3OFT&ACTORS

2EQUIREMENTSOF0ROGRAMMINGINTHE,ARGE

XI

■ #/.4%.43

5NIFORMITYTHROUGH#ONVENTIONS !BBREVIATIONS 0RE AND3UFFIXESFOR0,31,)DENTIFIERS

-ODULARIZATIONOF#ODEAND$ATA 0ACKAGESAND!SSOCIATED4ABLESAS-ODULES -ODULES#ONTAINING-ULTIPLE0ACKAGESOR3UBMODULES 3CHEMASAS-ODULES -ODULARIZATIONWITHIN3CHEMAS -ODULARIZATIONWITH3CHEMASVSWITHIN3CHEMAS

/BJECT /RIENTED0ROGRAMMINGWITH0,31, /BJECT /RIENTED0ROGRAMMINGWITH5SER $EFINED4YPES /BJECT /RIENTED0ROGRAMMINGWITH0,31,2ECORDS !SSESSMENT

-EMORY-ANAGEMENT -EASURING-EMORY5SAGE #OLLECTIONS

3UMMARY ■#HAPTER%VOLUTIONARY$ATA-ODELING ,ESSONSFROM4WO$ECADESOF3YSTEM$EVELOPMENT 4HE$ATABASEAND!GILE$EVELOPMENT %VOLUTIONARY$ATA-ODELING 2EFACTORINGTHE$ATABASE #REATINGAN!CCESS,AYERVIA0,31, 4HE!GILE-ANIFESTO 5SING0,31,WITH%VOLUTIONARY$ATA-ODELING $EFINETHE)NTERFACE 4HINK%XTENSIBLE

XII

■ #/.4%.43

4EST$RIVEN$EVELOPMENT 5SE3CHEMASAND5SERS7ISELY

3UMMARY ■#HAPTER0ROFILINGFOR0ERFORMANCE 7HAT)S0ERFORMANCE &UNCTIONAL2EQUIREMENTS 2ESPONSE4IME 4HROUGHPUT 2ESOURCE5TILIZATION 0ERFORMANCE)SA&EATURE

7HAT)S0ROFILING 3EQUENCE$IAGRAMS 4HE-AGICOF0ROFILES "ENEFITSOF0ROFILING

)NSTRUMENTATION 7HYIS4HIS0ROGRAM3LOW -EASUREMENT)NTRUSION )DENTIFICATION #ONDITIONAL#OMPILATION "UILT IN0ROFILERS %XTENDED31,4RACE$ATA%VENT  )NSTRUMENTATION,IBRARYFOR/RACLE),/ 

0ROBLEM$IAGNOSIS -ETHOD2 ),/%XAMPLE 0ROFILING%XAMPLE

3UMMARY

XIII

■ #/.4%.43

■#HAPTER#ODING#ONVENTIONSAND%RROR(ANDLING 7HYCODINGCONVENTIONS &ORMATTING #ASE #OMMENTS )NDENTATION

$YNAMIC#ODE 0ACKAGES 3TORED0ROCEDURES .AMING 0ARAMETERS #ALLS ,OCAL6ARIABLES #ONSTANTS 4YPES 'LOBAL6ARIABLES ,OCAL0ROCEDURESAND&UNCTIONS 0ROCEDURE-ETADATA

&UNCTIONS %RROR(ANDLING %RROR4RAPPING %RROR2EPORTING %RROR2ECOVERY 4EST&IRST$ISPLAY3ECOND

3UMMARY

XIV

■ #/.4%.43

■#HAPTER$EPENDENCIESAND)NVALIDATIONS $EPENDENCY#HAINS 3HORTENING$EPENDENCY#HAINS $ATATYPE2EFERENCE 6IEWFOR4ABLE!LTERATIONS !DDING#OMPONENTSINTO0ACKAGES 3YNONYMSIN$EPENDENCY#HAINS 2ESOURCE,OCKING &ORCING$EPENDENCYIN4RIGGERS #REATING4RIGGERS$ISABLED)NITIALLY 3UMMARY

)NDEX

XV



About the Authors ■*OHN"ERESNIEWICZISACONSULTINGMEMBEROFTHETECHNICALSTAFFAT/RACLEHEADQUARTERSIN2EDWOOD 3HORES #!(EJOINED/RACLEINTOWORKON%NTERPRISE-ANAGERINTHEDATABASEPERFORMANCEAREA ANDHASPLAYEDSIGNIFICANTROLEINTHEDESIGNOF$IAGNOSTICAND4UNINGPACKS 2EAL!PPLICATION4ESTING 3UPPORT7ORKBENCH AND%XADATA(EHASBEENAFREQUENTSPEAKERONDATABASEPERFORMANCEAND 0,31,PROGRAMMINGOVERMANYYEARSAT/RACLE/PENWORLDANDOTHERCONFERENCES(EISCO AUTHOROF /RACLE"UILT IN0ACKAGES/2EILLY!SSOCIATES  WITH3TEVEN&EUERSTEINANDISAFOUNDINGMEMBER OFTHE/AK4ABLENETWORK

■!DRIAN"ILLINGTONISACONSULTANTINAPPLICATIONDESIGN DEVELOPMENT ANDPERFORMANCETUNINGWHO HASBEENWORKINGWITH/RACLEDATABASESSINCE(EISTHEMANBEHINDfff^aPR[TSTeT[^_Ta]Tc A WEBSITEFULLOF31,AND0,31,FEATURES UTILITIES ANDTECHNIQUESFOR/RACLEDEVELOPERS!DRIANISALSO AN/RACLE!#%ANDAMEMBEROFTHE/AK4ABLE.ETWORK(ELIVESINTHE5+WITHHISWIFE!NJIANDTHREE CHILDREN'EORGIA /LIVER AND)SABELLA

■-ARTIN"ÓCHIHASWORKEDSINCEAS,EAD3OFTWARE!RCHITECTFOR!VALOQ APROVIDEROFA STANDARDIZEDBANKINGSOFTWAREBUILTONTHE/RACLE2$"-3WITHMILLIONLINESOF0,31,CODE 4OGETHERWITHTWOCOLLEAGUESHEDEFINESTHESYSTEMARCHITECTUREANDREVIEWSTHEDESIGNSANDCODEOF FULL TIME0,31,DEVELOPERS LOOKINGFORSIMPLICITY EFFICIENCY ANDROBUSTNESS-ARTINREGULARLYSPEAKS AT/RACLECONFERENCES)NHEWASNAMED0,31,$EVELOPEROFTHE9EARBY/RACLE-AGAZINE"EFORE GETTINGINTOTHE/RACLEDATABASE -ARTINWORKEDINOBJECT ORIENTEDSYSTEMS FORMALMETHODS AND APPROXIMATERECORDMATCHING(EHOLDSAN-3CFROMTHE3WISS&EDERAL)NSTITUTEOF4ECHNOLOGYANDA 0H$FROMTHE4URKU#ENTERFOR#OMPUTER3CIENCEIN&INLAND)NHISSPARETIME -ARTINENJOYSVARIOUS OUTDOORSPORTSWITHHISFAMILY

■-ELANIE#AFFREYISA3ENIOR$EVELOPMENT-ANAGERFOR/RACLE#ORPORATION PROVIDINGFRONT ENDAND BACK END/RACLESOLUTIONSFORTHEBUSINESSNEEDSOFVARIOUSCLIENTS3HEISCO AUTHOROFSEVERALTECHNICAL PUBLICATIONSINCLUDING/RACLE7EB!PPLICATION0ROGRAMMINGFOR0,31,$EVELOPERS /RACLE$"! )NTERACTIVE7ORKBOOK AND/RACLE$ATABASE!DMINISTRATION4HE#OMPLETE6IDEO#OURSE ALLPUBLISHEDBY 0RENTICE(ALL3HEHASINSTRUCTEDSTUDENTSIN#OLUMBIA5NIVERSITYgS#OMPUTER4ECHNOLOGYAND !PPLICATIONSPROGRAMIN.EW9ORK#ITY TEACHINGADVANCED/RACLEDATABASEADMINISTRATIONAND0,31, DEVELOPMENT3HEISAFREQUENT/RACLECONFERENCESPEAKER

■2ON#RISCOHASBEENASOFTWAREDESIGNER DEVELOPER ANDPROJECTLEADERFORYEARSANDHASWORKED WITH/RACLEDATABASESFORYEARS(EWORKSAT-ETHOD2#ORPORATION DESIGNINGANDDEVELOPING SOFTWARE MANAGINGSOFTWAREPRODUCTSLIKE-ETHOD20ROFILER -24OOLS AND-24RACE CONSULTING AND TEACHINGCOURSES(ISSPECIALTYISSIMPLIFYINGCOMPLEXWORK WHICHISESPECIALLYVALUABLEINHELPINGTHE PEOPLEAROUNDHIMACCOMPLISHEXTRAORDINARYTHINGS

XVI

■ !"/544(%!54(/23

■,EWIS#UNNINGHAMHASBEENWORKINGIN)4FOROVERYEARSANDHASWORKEDWITH/RACLEDATABASES SINCE(ISSPECIALTIESAREAPPLICATIONDESIGN DATABASEDESIGN ANDCODINGOFHIGHVOLUME 6,$" DATABASES(EISCURRENTLYA3ENIOR$ATABASE!RCHITECTATAFINANCIALSERVICESCOMPANYIN3T0ETERSBURG &,WORKINGONVERYLARGE HIGHTRANSACTIONRATEANALYTICALDATABASESANDAPPLICATIONS(ESPENDSAN INORDINATEAMOUNTOFTIMEKEEPINGUPWITHCURRENTTECHNOLOGYANDTRENDSANDSPEAKINGATUSERGROUPS ANDDOINGWEBINARS,EWISISALSOAN/RACLE!#%$IRECTORAND/RACLE#ERTIFIED0ROFESSIONAL(EHAS WRITTENSEVERALARTICLESFORTHE/RACLE4ECHNOLOGY.ETWORKANDMAINTAINSAN/RACLETECHNOLOGYBLOGAT Wcc_)Xcc^^[Q^gR^\Q[^Vb^aPR[TVdXST,EWISHASWRITTENTWOBOOKS%NTERPRISE$"4HE$EFINITIVE 2EFERENCE2AMPANT4ECHPRESS  AND31,$-,4HE31,3TARTER3ERIES#REATE3PACE  (ELIVES IN&LORIDAWITHHISWIFEANDTWOSONS9OUCANCONTACTHIMATLEWISC DATABASEWISDOMCOM

■$OMINIC$ELMOLINOISTHE,EAD/RACLEAND$ATABASE4ECHNOLOGISTFOR!GILEX4ECHNOLOGIES A CONSULTINGFIRMSPECIALIZINGINASSISTINGGOVERNMENTANDPRIVATEENTERPRISESTOREALIZETHEVALUEOFTHEIR INFORMATION$OMINICHASOVERYEARSOFDATABASEEXPERIENCE INCLUDINGMORETHANYEARSASAN /RACLE$ATABASE%NGINEERINGAND$EVELOPMENTPROFESSIONAL(EISAMEMBEROFTHE/AK4ABLE.ETWORK ANDREGULARLYPRESENTSATCONFERENCES SEMINARS ANDUSERGROUPMEETINGSIN%UROPEANDTHE53(EALSO MAINTAINSfff^aPR[T\dbX]VbR^\ ASITEFOCUSEDONDATABASECODINGANDDESIGNPRACTICESRELATEDTO DATABASEAPPLICATIONDEVELOPMENT$OMINICHOLDSA"ACHELOROF3CIENCEDEGREEINCOMPUTERSCIENCE FROM#ORNELL5NIVERSITY )THACA .9

■3UE(ARPERISA0RODUCT-ANAGERFOR/RACLE31,$EVELOPERAND31,$EVELOPER$ATA-ODELERINTHE $ATABASE$EVELOPMENT4OOLSGROUP3HEHASBEENAT/RACLESINCEANDISCURRENTLYBASEDIN ,ONDON3UEISAREGULARCONTRIBUTORTOMAGAZINES MAINTAINSATECHNICALBLOG ANDSPEAKSATMANY CONFERENCESAROUNDTHEWORLD3HEHASAUTHOREDTHETECHNICALBOOK/RACLE31,$EVELOPER0ACKT 0UBLISHING  7HENNOTATWORK 3UEISAKEENWALKERANDPHOTOGRAPHER3UETAKESTIMEOUTTOWORK WITHACHARITYINTHESLUMSOF.EW$ELHI WHERESHEWORKSWITHTHEWOMENANDCHILDREN

■4ORBEN(OLMHASBEENINTHECOMPUTERBUSINESSASADEVELOPERSINCE(EHASBEENWORKINGWITH /RACLESINCEHISFIRSTFOURYEARSASSYSTEMANALYSTANDAPPLICATIONDEVELOPER/RACLEAND&ORMS 2EPORTSAND$"! THENTWOYEARSASDEVELOPER/RACLE &ORMSAND204 AND$"! (E SPENTSEVERALYEARSWORKINGFOR/RACLE$ENMARKINTHE0REMIUM3ERVICESGROUPASA3ENIOR0RINCIPAL #ONSULTANTPERFORMINGAPPLICATIONDEVELOPMENTAND$"!TASKS(EALSOWORKEDASANINSTRUCTORIN 0,31, 31, AND$"!COURSES4ORBENNOWWORKSFOR-IRACLE!3fff\XaPR[TPbSZ ASACONSULTANT WITHAFOCUSINAPPLICATIONDEVELOPMENT0,31, MOD?PLSQL &ORMS !$& ANDDATABASEADMINISTRATION (EHASBEENAT-IRACLE!3YEARS(EISAN/RACLE#ERTIFIED$EVELOPERANDAMEMBEROF>PZCPQ[T]Tc

■#ONNOR-C$ONALDHASWORKEDWITH/RACLESINCETHEEARLYS CUTTINGHISTEETHON/RACLEVERSIONS AND/VERTHEPASTYEARS #ONNORHASWORKEDWITHSYSTEMSIN!USTRALIA THE5+ 3OUTHEAST!SIA 7ESTERN%UROPE ANDTHE5NITED3TATES(EHASCOMETOREALIZETHATALTHOUGHTHESYSTEMS ANDMETHODOLOGIESAROUNDTHEWORLDAREVERYDIVERSE THERETENDTOBETWOCOMMONTHEMESINTHE DEVELOPMENTOFSYSTEMSRUNNINGON/RACLEEITHERTOSTEERAWAYFROMTHE/RACLE SPECIFICFUNCTIONSORTO USETHEMINAHAPHAZARDORLESS THAN OPTIMALFASHION)TWASTHISOBSERVATIONTHATLEDTOTHECREATIONOF APERSONALHINTSANDTIPSWEBSITEfff^aPR[TSQPR^dZ ANDMOREPRESENTINGONTHE/RACLESPEAKER CIRCUITINANENDEAVORTOIMPROVETHEPERCEPTIONANDUSAGEOF0,31,INTHEINDUSTRY

XVII

■ !"/544(%!54(/23

■!RUP.ANDAHASBEENAN/RACLE$"!SINCE WHICHHASEXPOSEDHIMTOALLFACETSOFDATABASE ADMINISTRATION FROMMODELINGTODISASTERRECOVERY(ECURRENTLYLEADSTHEGLOBAL$"!TEAMAT3TARWOOD (OTELS THEPARENTOFCHAINSSUCHAS3HERATONAND7ESTIN IN7HITE0LAINS .9(ESERVESASA CONTRIBUTINGEDITOROF3%,%#4*OURNAL THEPUBLICATIONOF)NDEPENDENT/RACLE5SERS'ROUP)/5'  SPEAKSATMANY/RACLE4ECHNOLOGYEVENTSSUCHAS/RACLE7ORLDANDLOCALUSERGROUPSSUCHAS.EW9ORK /RACLE5SER'ROUPANDHASWRITTENMANYARTICLESFORBOTHPRINTPUBLICATIONSSUCHAS/RACLE-AGAZINE ANDONLINEPUBLICATIONSSUCHAS/RACLE4ECHNOLOGY.ETWORK!RUPHASCOAUTHOREDTWOBOOKS/RACLE 0RIVACY3ECURITY!UDITING2AMPANT  AND/RACLE0,31,FOR$"!S/g2EILLY  2ECOGNIZINGHIS PROFESSIONALACCOMPLISHMENTSANDCONTRIBUTIONSTOUSERCOMMUNITY /RACLECHOSEHIMASTHE$"!OF THE9EARIN!RUPLIVESIN$ANBURY #ONNECTICUT WITHHISWIFE!NINDITAANDSON!NISH(ECANBE REACHEDATARUP PROLIGENCECOM

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XVIII

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XIX



About the Technical Reviewers ■#HRIS"ECKHASADEGREEINCOMPUTERSCIENCEFROM2UTGERS5NIVERSITYANDHASBEENWORKINGWITH MULTIPLE$"-3SFORMORETHANYEARS(EHASSPENTTHELASTYEARSASAN/RACLEEMPLOYEEWHEREHE ISCURRENTLYA-ASTER0RINCIPAL4ECHNOLOGISTFOCUSINGONCOREDATABASETECHNOLOGIES(EISACO INVENTOR OFTWO530ATENTSONSOFTWAREMETHODOLOGIESTHATWERETHEBASISFORWHATISNOWKNOWNAS/RACLE !PPLICATION%XPRESS#HRISHASREVIEWEDOTHER/RACLEBOOKSINCLUDING%XPERT/NE /N /NE0EER )NFORMATION)NC  AND%XPERT/RACLE$ATABASE!RCHITECTURE!PRESS  BOTHBY4OM+YTEANDIS HIMSELFTHECO AUTHOROFTWOBOOKS "EGINNING/RACLE0ROGRAMMING7ROX0RESS  AND-ASTERING /RACLE0,31,!PRESS  (ERESIDESIN.ORTHERN6IRGINIAWITHHISWIFE-ARTAANDFOURCHILDREN WHENNOTSPENDINGTIMEWITHTHEM HECANUSUALLYBEFOUNDWASTINGTIMEPLAYINGVIDEOGAMESOR WATCHING3ERIES!FOOTBALL

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XX



Introduction 2ARELYDO)TAKETHEOPPORTUNITYTOINTRODUCEABOOKTHAT)VEHELPEDCREATE.ORMALLY)AMCONTENTWITH MYPLACEINTHEBACKGROUNDWHEREBOOKEDITORSRIGHTFULLYBELONG)MAKEANEXCEPTIONTHISTIMEBECAUSE THECONTENTINTHISBOOKBRINGSBACKSOMANYMEMORIESFROMOWNEXPERIENCESASADEVELOPERINDAYS GONEBY %XPERT0,31,0RACTICESISABOUTWIELDING0,31,EFFECTIVELY)TSNOTABOOKABOUTSYNTAX)TSABOOK ABOUTHOWTOAPPLYSYNTAXANDFEATURESALONGWITHGOODDEVELOPMENTPRACTICESTOCREATEAPPLICATIONS THATARERELIABLEANDSCALABLEˆANDMAINTAINABLEOVERTHELONGTERM 7ITHANYTOOL ONEOFTHEFIRSTTHINGSTOKNOWISWHENTOWIELDIT2IYAJ3HAMSUDEENDEFTLYTACKLESTHE QUESTIONOFWHENTOUSE0,31,INHISOPENINGCHAPTER$O.OT5SE
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XXI

■ ).42/$5#4)/.

!RUP.ANDAHELPSYOUGETCONTROLOVERDEPENDENCIESANDINVALIDATIONS$EPENDENCYISSUESCANBEA SOURCEOFSEEMINGLYRANDOM DIFFICULT TO REPEATAPPLICATIONERRORS!RUPSHOWSHOWTOGETCONTROLOVER WHATMUSTINEVITABLYHAPPEN SOTHATYOUARENTCAUGHTOUTBYUNEXPECTEDERRORS 7ECOULDHARDLYLEAVEPERFORMANCEANDSCALABILITYOUTOFTHEPICTURE2ON#RISCOTALKSABOUT PROFILINGYOURCODETOFINDTHEGREATESTOPPORTUNITIESFOROPTIMIZATION!DRIAN"ILLINGTONTALKSABOUTTHE PERFORMANCEASPECTSOFINVOKING0,31,FROMWITHIN31,STATEMENTS#ONNOR-C$ONALDCOVERSTHE TREMENDOUSPERFORMANCEADVANTAGESAVAILABLEFROMBULK31,OPERATIONS !NUNUSUALASPECTOFSCALABILITYNOTOFTENTHOUGHTABOUTISTHATOFAPPLICATIONSIZEANDTHENUMBER OFDEVELOPERS)S0,31,SUITEDFORLARGE SCALEDEVELOPMENTINVOLVINGDOZENS PERHAPSHUNDREDSOF PROGRAMMERS-ARTIN"ÓCHISHOWSTHAT0,31,ISVERYMUCHUPTOTHETASKINHISCHAPTERON0,31, PROGRAMMINGINTHELARGEBYRECOUNTINGHISSUCCESSWITHAN MILLIONLINEAPPLICATIONMAINTAINEDBY OVERDEVELOPERS 9OUCANPROBABLYTELLTHAT)MEXCITEDABOUTTHISBOOK4HEAUTHORSARETOPNOTCH%ACHHASWRITTEN ONANASPECTOF0,31,THATTHEYAREPASSIONATEANDESPECIALLYKNOWLEDGEABLEABOUT)FYOUREPASTTHE POINTOFLEARNINGSYNTAX THENSITDOWN READTHISBOOK ANDSTEPUPYOURGAMEINDELIVERINGAPPLICATIONS USINGTHEFULLPOWEROF0,31,AND/RACLE$ATABASE

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XXII

C HAP T E R 1



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