ISO/IEC 19075-3:2021

INTERNATIONAL ISO/IEC
STANDARD 19075-3
First edition
2021-08
Information technology — Guidance
for the use of database language
SQL —
Part 3:
SQL embedded in programs using the
TM
Java programming language
Technologies de l'information — Recommandations pour l'utilisation
du langage de base de données SQL —
Partie 3: SQL intégré dans des programmes utilisant le langage de
TM
programmation de Java
Reference number
©
ISO/IEC 2021
© ISO/IEC 2021
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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Email: copyright@iso.org
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Published in Switzerland
ii © ISO/IEC 2021 – All rights reserved

ISO/IEC19075-3:2021(E)
Contents Page
Foreword.v
Introduction.vii
1 Scope.1
2 Normativereferences.2
3 Termsanddefinitions.3
4 UseofSQLinprogramswritteninJava.4
4.1 ContextofSQLprogramswritteninJava.4
4.2 Designgoals.4
4.3 AdvantagesofSQL/OLBoverJDBC.4
4.4 ConsistencywithexistingembeddedSQLlanguages.5
4.5 Profilecustomizationoverview.5
4.5.1 Introductiontoprofilecustomization.5
4.5.2 Profilecustomizationprocess.6
4.5.3 Profilecustomizationutilities.7
4.6 Examples.7
4.6.1 Exampleofprofilegenerationandnaming.7
4.6.2 ExampleofaJARmanifestfile.7
4.6.3 Host variables.8
4.6.4 Hostexpressions.8
4.6.5 SQL/OLBclauses.8
4.6.6 Connection contexts.9
4.6.7 Defaultconnectioncontext.9
4.6.8 Iterators.10
4.6.8.1 Positionalbindingstocolumns.10
4.6.8.2 Namedbindingstocolumns.10
4.6.8.3 Providingnamesforcolumnsofqueries.11
4.6.9 InvokingSQL-invokedroutines.12
4.6.10 UsingmultipleSQL/OLBcontextsandconnections.12
4.6.11 SQLexecutioncontrolandstatus.13
4.6.12 Multiplejava.sql.ResultSetobjectsfromSQL-invokedprocedurecalls.14
4.6.13 CreatinganSQL/OLBiteratorobjectfromajava.sql.ResultSetobject.15
4.6.14 Obtainingajava.sql.ResultSetobjectfromaniteratorobject.15
4.6.15 Workingwithuser-definedtypes.16
4.6.16 Batching.17
4.6.17 Example program.17
4.6.18 Hostvariabledefinition.18
Bibliography.20
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ISO/IEC19075-3:2021(E)
Index.21
iv ©ISO/IEC2021–Allrightsreserved

ISO/IEC19075-3:2021(E)
Foreword
ISO(theInternationalOrganizationforStandardization)andIEC(theInternationalElectrotechnical
Commission)formthespecializedsystemforworldwidestandardization.Nationalbodiesthatare
membersofISOorIECparticipateinthedevelopmentofInternationalStandardsthroughtechnical
committeesestablishedbytherespectiveorganizationtodealwithparticularfieldsoftechnicalactivity.
ISOandIECtechnicalcommitteescollaborateinfieldsofmutualinterest.Otherinternationalorganizations,
governmentalandnon-governmental,inliaisonwithISOandIEC,alsotakepartinthework.
Theproceduresusedtodevelopthisdocumentandthoseintendedforitsfurthermaintenanceare
describedintheISO/IECDirectives,Part1.Inparticular,thedifferentapprovalcriterianeededforthe
differenttypesofdocumentshouldbenoted.Thisdocumentwasdraftedinaccordancewiththeeditorial
rulesoftheISO/IECDirectives,Part2(seewww.iso.org/directivesorwww.iec.ch/mem-
bers_experts/refdocs).
Attentionisdrawntothepossibilitythatsomeoftheelementsofthisdocumentmaybethesubjectof
patentrights.ISOandIECshallnotbeheldresponsibleforidentifyinganyorallsuchpatentrights.Details
ofanypatentrightsidentifiedduringthedevelopmentofthedocumentwillbeintheIntroductionand/or
ontheISOlistofpatentdeclarationsreceived(seewww.iso.org/patents),ortheIEClistofpatent
declarationsreceived(seepatents.iec.ch).
Anytradenameusedinthisdocumentisinformationgivenfortheconvenienceofusersanddoesnot
constituteanendorsement.
Foranexplanationofthevoluntarynatureofstandards,themeaningofISOspecifictermsandexpressions
relatedtoconformityassessment,aswellasinformationaboutISO’sadherencetotheWorldTrade
Organization(WTO)principlesintheTechnicalBarrierstoTrade(TBT)seewww.iso.org/iso/fore-
word.html.IntheIEC,seewww.iec.ch/understanding-standards.
ThisdocumentwaspreparedbyTechnicalCommitteeISO/IECJTC1,Informationtechnology,Subcom-
mitteeSC32,Datamanagementandinterchange.
ThisfirsteditionofISO/IEC19075-3cancelsandreplacesISO/IECTR19075-3:2015.
ThisdocumentisintendedtobeusedinconjunctionwiththefollowingeditionsofthepartsoftheISO/IEC
9075series:
— ISO/IEC9075-1,sixtheditionorlater;
— ISO/IEC9075-2,sixtheditionorlater;
— ISO/IEC9075-3,sixtheditionorlater;
— ISO/IEC9075-4,seventheditionorlater;
— ISO/IEC9075-9,fiftheditionorlater;
— ISO/IEC9075-10,fiftheditionorlater;
— ISO/IEC9075-11,fiftheditionorlater;
— ISO/IEC9075-13,fiftheditionorlater;
— ISO/IEC9075-14,sixtheditionorlater;
— ISO/IEC9075-15,secondeditionorlater;
— ISO/IEC9075-16,firsteditionorlater.
©ISO/IEC2021–Allrightsreserved v

ISO/IEC19075-3:2021(E)
AlistofallpartsintheISO/IEC19075seriescanbefoundontheISOandIECwebsites.
Anyfeedbackorquestionsonthisdocumentshouldbedirectedtotheuser’snationalstandardsbody.A
completelistingofthesebodiescanbefoundatwww.iso.org/members.htmlandwww.iec.ch/-
national-committees.
vi ©ISO/IEC2021–Allrightsreserved

ISO/IEC19075-3:2021(E)
Introduction
Theorganizationofthisdocumentisasfollows:
1) Clause1,“Scope”,specifiesthescopeofthisdocument.
2) Clause2,“Normativereferences”,identifiesadditionalstandardsthat,throughreferenceinthis
document,constituteprovisionsofthisdocument.
3) Clause3,“Termsanddefinitions”,definesthetermsanddefinitionsusedinthisdocument.
4) Clause4,“UseofSQLinprogramswritteninJava”,providesatutorialontheembeddingofSQL
expressionsandstatementsinprogramswrittenintheJava™ programminglanguage.
1Java™isthetrademarkofaproductsuppliedbyOracle.Thisinformationisgivenfortheconvenienceofusersofthisdocument
anddoesnotconstituteanendorsementbyISOorIECoftheproductnamed.
©ISO/IEC2021–Allrightsreserved vii

INTERNATIONAL STANDARD ISO/IEC 19075-3:2021(E)
Informationtechnology—GuidancefortheuseofdatabaselanguageSQL—
Part3:
SQLembeddedinprogramsusingtheJava™programminglanguage
1 Scope
ThisdocumentdescribesthesupportfortheuseofSQLwithinprogramswritteninJava.
ThisdocumentdiscussesthefollowingfeaturesoftheSQLlanguage:
— TheembeddingofSQLexpressionsandstatementsinprogramswrittenintheJavaprogramming
language.
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ISO/IEC19075-3:2021(E)
2 Normativereferences
Thefollowingdocumentsarereferredtointhetextinsuchawaythatsomeoralloftheircontentconsti-
tutesrequirementsofthisdocument.Fordatedreferences,onlytheeditioncitedapplies.Forundated
references,thelatesteditionofthereferenceddocument(includinganyamendments)applies.
ISO/IEC9075-1,Informationtechnology—Databaselanguages—SQL—Part1:Framework
(SQL/Framework)
ISO/IEC9075-10,Informationtechnology—Databaselanguages—SQL—Part10:ObjectLanguage
Bindings(SQL/OLB)
JavaCommunityProcess.TheJava™LanguageSpecification[online].JavaSE13Edition.Redwood
Shores,California,USA:Oracle,Availableathttps://docs.oracle.com/javase/specs/jls/-
se13/jls13.pdf
JavaCommunityProcess.JDBC™4.3Specification[online].Edition4.3.RedwoodShores,California,
USA:Oracle,Availableathttps://download.oracle.com/otn-pub/jcp/-
jdbc-4_3-mrel3-eval-spec/jdbc4.3-fr-spec.pdf
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ISO/IEC19075-3:2021(E)
3 Termsanddefinitions
Forthepurposesofthisdocument,thetermsanddefinitionsgiveninISO/IEC9075-1apply.
ISOandIECmaintainterminologicaldatabasesforuseinstandardizationatthefollowingaddresses:
— IECElectropedia:availableathttp://www.electropedia.org/
— ISOOnlinebrowsingplatform:availableathttp://www.iso.org/obp
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ISO/IEC19075-3:2021(E)
4 UseofSQLinprogramswritteninJava
4.1 ContextofSQLprogramswritteninJava
TherequirementsforthematerialdiscussedinthisdocumentshallbeasspecifiedinISO/IEC9075-1
andISO/IEC9075-10.
4.2 Designgoals
ThefollowingitemsrepresentthemajordesignfeaturesofISO/IEC9075-1.ISO/IEC9075-10,Java,and
JDBCallspecifyrequirementsforthematerialdiscussedinthisdocument.
— Provideaconcise,legiblemechanismforembeddingSQL-statementsinaprogramthatotherwise
conformstoJava.
— SyntacticandsemanticcheckofSQL-statementspriortoprogramexecution.
SQL/OLBcanuseanimplementation-definedmechanismattranslatetimetocheckembeddedSQL-
statementstomakesurethattheyaresyntacticallyandsemanticallycorrect.
— AllowthesyntaxandsemanticsofSQL-statementstobelocation-independent.
ThesyntaxandsemanticsofSQL-statementsinanSQL/OLBprogramdonotdependontheconfigu-
rationunderwhichSQL/OLBisrunning.ThismakesitpossibletoimplementSQL/OLBprograms
thatrunontheclient,intheSQL-server,orinamiddletier.
— ProvidefacilitiesthatenabletheprogrammertomovebetweentheSQL/OLBandJDBCenvironments
bysharingasingleSQL-connectioninbothenvironments.
— ProvideforbinaryportabilityoftranslatedandcompiledJavaSQL-clientapplicationssuchthatthey
canbeusedtransparentlywithmultipleSQL-servers.Inaddition,binaryportabilityprofilesallow
forcustomizationandoptimizationofSQL-statementswithinanSQL/OLBapplication.
4.3 AdvantagesofSQL/OLBoverJDBC
JDBCprovidesacomplete,low-levelSQLinterfacefromJavatoSQL-implementations.SQL/OLBisdesigned
tofillacomplementaryrolebyprovidingahigher-levelprogramminginterfacetoSQL-implementations
insuchamannerastofreetheprogrammerfromthetediousandcomplexprogramminginterfacesfound
inlower-levelAPIs.
Thefollowingaresomemajordifferencesbetweenthetwo:
— SQL/OLBsourceprogramsaresmallerthanequivalentJDBCprogramssincethetranslatorcan
implicitlyhandlemanyofthetediousprogrammingchoresthatdynamicinterfacesrequire.
— SQL/OLBprogramscantype-checkSQLcodeattranslatetimeusinganimplementation-dependent
mechanism.JDBC,beingacompletelydynamicAPI,cannot.
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ISO/IEC19075-3:2021(E)
4.3 AdvantagesofSQL/OLBoverJDBC
— SQL/OLBprogramsallowdirectembeddingofJavahostexpressionswithinSQL-statements.JDBC
requiresaseparatecallstatementforeachbindvariableandspecifiesthebindingbypositionnumber.
— SQL/OLBenforcesstrongtypingofqueryoutputsandvaluesreturnedandallowstypecheckingon
calls.JDBCpassesvaluestoandfromSQLwithoutcompiletimetypechecking.
— SQL/OLBprovidessimplifiedrulesforinvokingSQL-invokedroutines.JDBCrequiresagenericcall
toanSQL-invokedroutine,fun,tohavethefollowingsyntax:
prepStmt.prepareCall("{call fun(.)}");    // For SQL-invoked procedures
prepStmt.prepareCall("{? = call fun(.)}");  // For SQL-invoked functions
SQL/OLBprovidessimplifiednotations:
#sql { CALL fun(.) };       // SQL-invoked procedure
// Declare x
...
#sql x = { VALUES(fun(.)) };    // SQL-invoked function
// VALUES is an SQL construct
4.4 ConsistencywithexistingembeddedSQLlanguages
ProgramminglanguagescontainingembeddedSQLarecalledhostlanguages.Javadiffersfromthetradi-
tionalhostlanguages(Ada,C,COBOL,Fortran,MUMPS(M),Pascal,PL/I)inwaysthatsignificantlyaffect
itsembeddingofSQL.
— Javahasautomaticstoragemanagement(alsoknownas“garbagecollection”)thatsimplifiesthe
managementofstoragefordataretrievedfromSQL-implementations.
— AllJavatypesrepresentingcompositedata,anddataofvaryingsizes,haveadistinguishedvalue
null,whichcanbeusedtorepresenttheSQLNULLvalue.ThisgivesJavaprogramsanalternative
totheindicatorvariablesthatarepartoftheinterfacestootherhostlanguages.
— Javaisdesignedtosupportprogramsthatareautomaticallyheterogeneouslyportable(alsocalled
“superportable”orsimply“downloadable”).That,alongwithJava’stypesystemofclassesand
interfaces,enablescomponentsoftware.Inparticular,anSQL/OLBtranslator,writteninJava,can
callcomponentsthatarespecializedbySQL-implementations,inordertoleveragetheexisting
authorization,schemachecking,typechecking,transactional,andrecoverycapabilitiesthataretra-
ditionalofSQL-implementations,andtogeneratecodeoptimizedforparticularSQL-implementations.
— Javaisdesignedforbinaryportabilityinheterogeneousnetworks,whichpromisestoenablebinary
portabilityforapplicationsthatuseSQL.
— SQL/OLBextendsthetraditionalconceptofembeddedhostvariablesbyallowinggeneralizedhost
expressions.
4.5 Profilecustomizationoverview
4.5.1 Introductiontoprofilecustomization
Thissubclausedescribeshowimplementation-specific“customized”SQLexecutioncontrolcanbeadded
toSQL/OLBapplications.TheSQL/OLBruntimeframeworkusesthefollowinginterfaces:
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ISO/IEC19075-3:2021(E)
4.5 Profilecustomizationoverview
— SQLJ.runtime.profile.RTStatementtoexecuteSQL-statements.
— SQLJ.runtime.profile.RTResultSettodescribequeryresults.
— SQLJ.runtime.profile.ConnectedProfiletocreateRTStatementobjectscorrespondingtoparticular
SQL-statements.
AnSQL-implementationisabletocontrolSQLexecutionbyprovidinganimplementationofthe
RTStatement,RTResultSet,andConnectedProfileinterfaces.AnSQL-implementationisabletoredirect
controltoitsowncodebyregisteringcustomizationhookswiththeapplicationprofiles.
Forexample,iftheclientconnectstoSQL-serverA,thenacustomizationthatunderstandsSQL-server
A’ssystemwillbeused.IftheclientconnectstoSQL-serverB,thenSQL-serverB’scustomizationwillbe
used.Intheabsenceofaconnectionspecificcustomization,thedefaultJDBCbasedcustomizationwill
beused.Liketheprofileobject,customizationobjectsareserializable.Thisallowsthecustomization
statetobestoredandrestoredwiththeprofile.Inthismanner,animplementation-dependentdeployment
toolisabletoloadtheprofile,inspectandprecompiletheSQL-statementsitcontains,registeran
appropriatecustomization,andstoretheprofileinpersistentstorage.Thenatapplicationruntime,the
profileandtheregisteredimplementation-dependentcustomizationwillbothberestored,andthecus-
tomizationwillbeusedtoexecutetheSQL-statements.
4.5.2 Profilecustomizationprocess
Theprofilecustomizationprocessistheactofregisteringprofilecustomizationobjectswiththeprofile(s)
associatedwithanapplication.Theprofilecustomizationprocesscanbegeneralizedtothefollowing
steps:
1) DiscovertheprofileobjectswithinaJARfile.
2) Foreachprofile,deserializetheprofileobjectfromtheappropriateJARentry.
3) CreateanSQL-connectionwithwhichtheprofilewillbecustomized.
4) Createandregisteraprofilecustomizationwiththeprofile.
5) Serializethecustomizedprofilebacktopersistentstorage.
6) RecreatetheJARcontentsusingthecustomizedserializedprofiles.
Oftheabovesteps,onlyStep4)islikelytochangefromSQL-implementationtoSQL-implementation.
WhileStep3)isimplementation-dependent,itcanbedoneusingaparameterizedtoolandJDBC.The
restofthestepsinvolveactionsthatcanbeperformedbyanygenericutilitywithoutspecificknowledge
ofthecustomizationbeingperformed.
Theactofcreatingandregisteringacustomizationobjectwithaprofile(step4above)isabstractly
definedbytheJavainterfaceSQLJ.runtime.profile.util.ProfileCustomizer.Theintentofdefiningthis
interfaceistoallowSQL-implementationstoconcentrateonwritingprofilecustomizersandcustomization
objects(step4above),whiletoolsandapplicationimplementationsconcentrateonwritinggenerictools
thatapplycustomizerstoapplicationprofiles(steps1–3and5–6above).
Theprofilecustomizerinterfaceisabletosupportmostcustomizationregistrationrequirements.However,
itisnotrequiredthatallutilitiesthatregistercustomizationobjectswithaprofileimplementthisinterface.
SQL/OLBapplicationswillbeabletorunandleverageallimplementation-specificcustomizationobjects
registeredwithaprofile,regardlessofwhetherornottheywereregisteredbyaprofilecustomizer.The
primarybenefitofconformingtotheprofilecustomizerinterfaceistobeabletotakeadvantageof
existingandfutureautomatedprofilecustomizationutilitiesthatareabletoload,callandmanipulate
profilecustomizers.
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ISO/IEC19075-3:2021(E)
4.5 Profilecustomizationoverview
4.5.3 Profilecustomizationutilities
Profilecustomizerscanbeinstantiatedandusedbyautomatedgeneral-purposeprofilecustomization
utilities.AnSQL-implementationmightincludeacommand-linebasedtoolthatservesasacustomization
utilityprototype.Inadditiontoacommandline-basedutility,otherusefulcustomizationutilitiesmight
include:
— GUI-basedIDEsusedtodrag-and-dropcustomizationsintoprofiles.
— TightintegrationofcustomizationutilitieswithSQL-implementationstoautomaticallycustomize
theprofilesloadedintotheSQL-server.
— Background“SQL/OLBinstaller”processusedasadministrativetooltodiscoverandcustomize
SQL/OLBapplicationsforavailableSQL-schemas.
NOTE1—Implementorsareencouragedtoimplementutilitiesusingtheseandotherideas.Makingsuchtoolspublicly
availablewillgreatlybenefitandfacilitatetheSQL/OLBbinary-portabilityeffort.
4.6 Examples
4.6.1 Exampleofprofilegenerationandnaming
Supposethereexiststhefollowingfile,Bar.SQLJ,whichdefinespackageCOM.foo,andcontainsthree
sassociatedwithtwos.
package COM.foo;
#sql context MyContext;
public class Bar
{
public static void doSQL(MyContext ctx) throws SQLException
{
// 1: explicit context
#sql [ctx] { UPDATE TAB1 SET COL1 = COL1 + 2 };
// 2: implicit context
#sql { INSERT INTO TAB2 VALUES(3, 'Hello there') };
// 3: explicit context again
#sql [ctx] { DELETE FROM TAB1 WHERE COL1 > 500 };
}
}
Twoprofilesarecreatedforthisfile;theyarenamedCOM.foo.Bar_SJProfile0andCOM.foo.Bar_SJPro-
file1.COM.foo.Bar_SJProfile0containsinformationdescribings1and3,andis
storedinafilecalledBar_SJProfile0.ser.Com.foo.Bar_SJProfile1describesclause2,andisstoredin
fileBar_SJProfile1.ser.
4.6.2 ExampleofaJARmanifestfile
WorkingagainwiththefileBar.SQLJfromthelastexample,iftheBarapplicationwerepackagedfor
deploymentasaJARfile,theJAR’smanifestcanbeusedbySQL/OLBcustomizationutilitiestolocatethe
application’sprofilefiles.Toallowthatuse,theprofilesectionofthemanifestfilewouldhavethefollowing
entries:
— Name:COM/foo/Bar_SJProfile0.serSQLJProfile:TRUE
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ISO/IEC19075-3:2021(E)
4.6 Examples
— Name:COM/foo/Bar_SJProfile1.serSQLJProfile:TRUE
4.6.3 Hostvariables
Thefollowingquerycontainshostvariable:x(whichistheJavavariable,Javafield,orparameterxvisible
inthescopecontainingthequery):
SELECT COL1, COL2 FROM TABLE1 WHERE :x > COL3
4.6.4 Hostexpressions
Hostexpressionsareevaluatedfromlefttorightandcancausesideeffects.Forexample:
SELECT COL1, COL2 FROM TABLE1 WHERE :(x++) > COL3
HostexpressionsarealwayspassedtoandretrievedfromtheSQL-serverusingpurevaluesemantics.
Forinstance,intheaboveexample,thevalueofx++isdeterminedpriortostatementexecutionandits
determinedvalueisthevaluethatispassedtotheSQL-serverforstatementexecution.
SELECT COL1, COL2 FROM TABLE1 WHERE :(x[--i]) > COL3
Intheaboveexample,priortostatementexecution,thevalueofiisdecrementedby1(one)andthen
thevalueofthei-thelementofxisdeterminedandpassedtotheSQL-serverforstatementexecution.
ConsiderthefollowingexampleofanSQL/PSM:
SET :(z[i++]) = :(x[i++]) + :(y[i++])
Assumethatihasaninitialvalueof1(one).Hostexpressionsareevaluatedinlexicalorder.
Therefore,thearrayindexusedtodeterminethelocationinthearrayzis1(one),afterwhichthevalue
ofiisincrementedby1(one).Consequently,thearrayindexusedtodeterminethelocationinthearray
xis2,afterwhichthevalueofiisincrementedby1(one).Asaresult,thearrayindexusedtodetermine
thelocationinthearrayyis3,afterwhichthevalueofiisincrementedby1(one).Thevalueofiinthe
Javaspaceisnow4.Thestatementisthenexecuted.Afterstatementexecution,theoutputvalueisassigned
toz[1].
Assignmentstooutputhostexpressionsarealsoperformedinlexicalorder.Forexample,considerthe
followingcalltoanSQL-invokedprocedurefoothatreturnsthevalues2and3.
CALL foo( :OUT x, :OUT x )
Afterexecution,xhasthevalue3.
4.6.5 SQL/OLBclauses
ThefollowingSQL/OLBclauseispermittedtoappearwhereveraJavastatementcanlegallyappearand
itspurposeistodeletealloftherowsinthetablenamedTAB:
#sql { DELETE FROM TAB };
ThefollowingJavamethod,wheninvoked,insertsitsargumentsintoanSQLtable.Themethodbody
consistsofanSQL/OLBexecutableclausecontainingthehostexpressionsx,y,andz.
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ISO/IEC19075-3:2021(E)
4.6 Examples
void m (int x, String y, float z) throws SQLException
{
#sql { INSERT INTO TAB1 VALUES (:x, :y, :z ) };
}
Thefollowingmethodselectstheaddressofthepersonwhosenameisspecifiedbytheinputhost
expressionnameandthenretrievesanassociatedaddressfromtheassumedtablePEOPLE,withcolumns
NAMEandADDRESS,intotheoutputhostexpressionsaddr,whereitisthenpermittedtobeused,for
example,inacalltoSystem.out.println:
void print_address (String name) throws SQLException
{
String addr;
#sql { SELECT ADDRESS INTO :addr
FROM PEOPLE
WHERE :name = NAME };
}
4.6.6 Connectioncontexts
InthefollowingSQL/OLBclause,theconnectioncontextisthevalueoftheJavavariablemyconn.
#sql [myconn] { SELECT ADDRESS INTO :addr
FROM PEOPLE
WHERE :name = NAME } ;
ThefollowingillustratesanSQL/OLBconnectionclausethatdefinesaconnectioncontextclassnamed
“Inventory”:
#sql context Inventory;
4.6.7 Defaultconnectioncontext
IfaninvocationofanSQL/OLBtranslatorindicatesthatthedefaultconnectioncontextclassisclassGreen,
thenallSQL/OLBclausesthatusethedefaultconnectionwillbetranslatedasiftheyusedtheexplicit
connectioncontextobjectGreen.getDefaultContext( ).Forexample,thefollowingtwoSQL/OLBclauses
areequivalentifthedefaultconnectioncontextclassisclassGreen:
#sql { UPDATE TAB SET COL = :x };
#sql
...