ISO/IEC 39075:2024/Cor 1:2026

• Status: Published
• Publication Date: 30-Jul-2026
• ICS: 35.060 - Languages used in information technology
• Technical Committee: ISO/IEC JTC 1/SC 32 - Data management and interchange
• Drafting Committee: ISO/IEC JTC 1/SC 32/WG 3 - Database language
• Current Stage: 6060 - International Standard published
• Start Date: 31-Jul-2026
• Completion Date: 31-Jul-2026

• Corrects: ISO/IEC 39075:2024 - Information technology — Database languages — GQL
• Effective Date: 07-Jan-2026

Overview

ISO/IEC 39075:2024/Cor 1:2026, titled Information technology - Database languages - GQL - Technical Corrigendum 1, is published by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC). This technical corrigendum amends and clarifies ISO/IEC 39075:2024, which specifies GQL (Graph Query Language) as a database language standard. The corrigendum addresses essential corrections, clarifications, and enhancements in the normative framework and syntax rules for GQL, aiming to resolve ambiguities and ensure alignments in graph database implementations.

This update contributes significant value to organizations and vendors implementing GQL by refining definitions, syntax rules, and conformance requirements. It helps ensure interoperability, accuracy, and consistency in graph data management across various information technology environments.

Key Topics

• Corrections to GQL Catalog Structure: Updates to diagrams and descriptions to align graphical representations with normative text, improving clarity around GQL-environments, catalogs, directories, and schemas.
• Conformance and Feature Dependencies: Refined and clarified conformance rules, including conditional language features and mutual dependencies among features.
• Syntax and Semantic Clarifications: Extensive changes to syntax rules, such as node and edge type label definitions, property type identification, and adjustments to the structure of , , and constructs.
• Error and Exception Handling: Improved guidance on execution outcomes, error reporting, and handling partial results in edge cases, contributing to predictable query behavior and robust database system responses.
• List, Numeric, and Temporal Types: Adjustments to type handling, including list value rules, temporal types, and related exception and error management.
• Session Management Enhancements: Updated rules for session commands to ensure correct feature gating and conformance, making session behavior more predictable in multi-user environments.
• Feature Relationship Table Updates: Additions and deletions to the implied feature relationships for better modular implementation and clearer dependencies within GQL environments.

Applications

Organizations and database vendors using or implementing GQL as part of their graph database solutions directly benefit from adopting this corrigendum. The corrected and clarified rules:

• Enhance Interoperability: By aligning implementations with amended syntax and semantics, products from different vendors can operate seamlessly in heterogeneous environments.
• Reduce Implementation Errors: Developers and system architects gain clearer guidance, minimizing misinterpretations and ensuring conformance with the GQL standard.
• Support Feature Management: Conditional conformance rules allow vendors to develop modular database systems, activating only the necessary features for their use cases.
• Improve Data Integrity and Query Reliability: Changes in error handling and execution outcome specifications lead to more robust and predictable graph database operations.
• Facilitate Standards Compliance: Mandated for certification, audit, or procurement, adoption of the corrigendum ensures continued legal and operational adherence to evolving international IT standards.

Related Standards

• ISO/IEC 39075:2024 - Information technology - Database languages - GQL
  The core document for GQL language specifications.
• ISO/IEC 9075 - Information technology - Database languages - SQL
  Includes reference to SQL standards pertinent to database language features, complementing GQL.
• ISO/IEC JTC 1/SC 32 - Data management and interchange
  Technical committee responsible for drafting standards that relate to database languages, interoperability, and metadata exchange.

Implementing the changes in ISO/IEC 39075:2024/Cor 1:2026 is essential for any organization or developer committed to robust, consistent GQL-based systems and enterprise-level graph database solutions.

International
Standard
ISO/IEC 39075
First edition
Information technology — Database
2024-04
languages — GQL
TECHNICAL
TECHNICAL CORRIGENDUM 1
CORRIGENDUM 1
Technologies de l'information — Langages de base de données —
2026-07
GQL
RECTIFICATIF TECHNIQUE 1
Reference number
ISO/IEC 39075:2024/Cor. 1:2026(en) © ISO/IEC 2026

ISO/IEC 39075:2024/Cor. 1:2026(en)
© ISO/IEC 2026
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
© ISO/IEC 2026 – All rights reserved
ii
ISO/IEC 39075:2024/Cor.1:2026(en)
Technical Corrigendum 1 to ISO/IEC 39075:2024 was prepared by Joint Technical Committee ISO/IEC JTC 1,
Information technology, Subcommittee SC 32, Data management and interchange.
© ISO/IEC 2026 – All rights reserved
iii
ISO/IEC 39075:2024/Cor.1:2026(en)
4 Concepts
4.2 GQL-environmentsandtheircomponents
4.2.5 GQL-catalog
4.2.5.1 GeneraldescriptionoftheGQL-catalog
1. Rationale: Aligncurrentlymisleadingdiagramwiththenormativetext.
ReplaceFigure2,“ComponentsofaGQL-catalog”with:
©ISO/IEC2026–Allrightsreserved
ISOISO/IEC/IEC 3390759075:202:20244/C/Cor.or.1:21:202026(e6(enn))
GQL-catalog
root
isoneinstanceofeither
GQL-directory GQL-schema
holds
holds
holds
Primarycatalogobject
isa
Graph Binding Named
Graph
procedure
type table
includes includes
1.*
Node Edge
type type
isa
Secondarycatalogobject
Figure2—ComponentsofaGQL-catalog
4.2.5.3 GQL-schemas
1. Rationale: AddmissingFeaturerequiredforcorrectconformancespecification.
Replacethelastparagraphwith:
©ISO/IEC2026–Allrightsreserved
ISO/IEC 39075:2024/Cor.1:2026(en)
AGQL-implementationmayautomaticallypopulateaGQL-schemauponitscreationinanimplemen-
tation-defined(IW016)way.WithoutFeatureGC00,“Automaticgraphpopulation”,aconforming
GQL-implementationshallnotprovideaGQL-schemawithapre-populatedgraph.
4 Executioncontexts
4.8.4 Executionoutcomes
1. Rationale: AGQL-implementationmayhavealreadyreturnedpartialresultswhenanexceptioncondition
isidentified.
nd nd
Replacethe2 bulletofthe2 paragraphwith:
— Afailedoutcome,whichisanexecutionoutcomerecordinganexceptioncondition.Itis
implementation-dependent(UA003)whetherornotafailedoutcomereturnsapartialresult.
4.13 GQL-objecttypes
4.13.2 Graphtypesandgraphelementtypes
4.13.2.3 Nodetypes
1. Rationale: Definethenodetypelabels.
Insertthefollowingparagraphbeforethe3rdparagraph:
Anodetypelabelofagraphtypeisanylabelthatiscontainedinthenodetypelabelsetofatleast
onenodetypeofthegraphtype.
4.13.2.4 Edgetypes
1. Rationale: Definetheedgetypelabels.
Insertthefollowingparagraphbeforethe3rdparagraph:
Anedgetypelabelofagraphtypeisanylabelthatiscontainedintheedgetypelabelsetofatleast
oneedgetypeofthegraphtype.
4.13.2.5 Propertytypes
1. Rationale: Providethedefinitionofbeing“ofapropertytype”.
nd
Addthefollowingparagraphafterthe2 paragraph.
ApropertyPisofapropertytypePTifPandPThaveequalnamesandthevalueofPisofthevalue
typeofPT.
4.13.2.7 Structuralconsistencyofelementtypes
1. Rationale: CorrecttheFeaturecode.
rd
Replacethe3 paragraphwith:
©ISO/IEC2026–Allrightsreserved
ISO/IEC 39075:2024/Cor.1:2026(en)
Bothconsistencycriteriarelyonthegraph-typespecificcombinationofpropertyvaluetypestoensure
thatcertainpropertytypesofelementtypesofagraphtypethathavethesamenamealsoeither
havethesamevaluetypeor,ifFeatureGG26,“Relaxedpropertyvaluetypeconsistency”issupported,
havevaluetypesthatcanbecombinedbyanapplicationoftheSyntaxRulesofSubclause22.18,
“Generalcombinationofvaluetypes”toobtainasupportedpropertyvaluetype.
4.14 Dynamicuniontypes
4.14.4 Dynamicgenerationoftypetestsandcasts
4.14.4.2 Dynamicgenerationoftypetestsandstrictcastsfora
withoutoperands
1. Rationale: Removetheduplicationofexceptionconditions“dataexception—invalidvaluetype(22G12)”
and“dataexception—invalidvaluetype(22G03)”.
Replaceitem7)with:
7) LetERRORbeanimplementation-dependent(UV003)whoseevaluation
raisestheexceptioncondition:dataexception—invalidvaluetype(22G03).
4.14.4.3 Dynamicgenerationoftypetestsandstrictcastsforawith
operands
1. Rationale: Removetheduplicationofexceptionconditions“dataexception—invalidvaluetype(22G12)”
and“dataexception—invalidvaluetype(22G03)”.
Replaceitem5)with:
5) LetERRORbeanimplementation-dependent(UV003)whoseevaluation
raisestheexceptioncondition:dataexception—invalidvaluetype(22G03).
7 Sessionmanagement
7.1
1. Rationale: AddmissingConformanceRules.
AddthefollowingConformanceRule:
1.1) WithoutFeatureGS09,“SESSIONSETcommand:setsessionschema”,conformingGQLlanguage
shallnotcontaina.
1.2) WithoutFeatureGS17,“SESSIONSETcommand:setsessiongraph”,conformingGQLlanguage
shallnotcontaina.
7.2
1. Rationale: CorrecttwoConformanceRules.
ReplaceConformanceRules6)and7)with:
©ISO/IEC2026–Allrightsreserved
ISO/IEC 39075:2024/Cor.1:2026(en)
6) WithoutFeatureGS08,“SESSIONRESETcommand:resetallsessionparameters”,conforming
GQLlanguageshallnotcontainSESSIONRESETALLPARAMETERS.
7) WithoutFeatureGS16,“SESSIONRESETcommand:resetindividualsessionparameters”,
conformingGQLlanguageshallnotcontainathatcontainsa
.
7.3
1. Rationale: AddamissingConformanceRule.
AddthefollowingConformanceRule:
1) WithoutFeatureGS18,“SESSIONCLOSEcommand”,conformingGQLlanguage,shallnot
containa.
14 Querystatements
14.7
1. Rationale: Removeananarbitraryandpointlessrestriction.
DeleteSyntaxRule7).
2. Rationale: Addmissingsyntaxrulesneededtopreventabindingvariableontheleftsideofa definition>frombeingreferencedintheontherightsideofsomeother
inthesame.
ReplaceSyntaxRule11)with:
11) LetNbethenumberofsimmediatelycontainedinLVDL.
12) For1(one)≤i≤N,letCLbedefinedasfollows:
i
a) LetLVDbethei-thsimmediatelycontainedinLVDLaseffec-
i
tivelyreplacedbySyntaxRule3).
b) LetRIbethethatisimmediatelycontainedinthe i
definition>thatisLVD.
i
NOTE1—LVDissubjecttoSyntaxRule3).
i
c) CLis:
i
CALL (IBVRL) {
LVD
i
RETURN RI
i
}
d) LSiseffectivelyreplacedbythespace-separatedconcatenationofallCL,1(one)≤i≤
i
N.
©ISO/IEC2026–Allrightsreserved
ISO/IEC 39075:2024/Cor.1:2026(en)
3. Rationale: Add a missing Conformance Rule to make the alternative in the
anoptionalfeature.
AddthefollowingConformanceRule:
2) WithoutFeatureGP05,“Procedure-localvaluevariabledefinitions”,inconformingGQLlan-
guage,ashallnotcontaina.
14.10
1. Rationale: Ensurethatanisnotusedinaninappropriatecontext.
ReplaceSyntaxRule4)c)i)2)A)V)with:
4) .
c) .
i) .
2) .
A) .
V) IfRSdoesnotsimplycontainaanddoes
notdirectlycontainacontainingan gatefunction>,thennocontainedinOBCshall
containan.
2. Rationale: AddamissingConformanceRule.
AddthefollowingConformanceRule:
2) WithoutFeatureGQ27,“FINISHstatement”,conformingGQLlanguage,shallnotcontaina
thatisFINISH.
14.11
1. Rationale: SyntaxRule10a)definesGRISETasthesetofaliasescontainedinthethen
definesARISETasthesetofaliasesforaggregatingreturnitemsthatarenotcontainedin
GRISET.Thisallowsanaliasforaggregatingreturnitemtobeincorrectlyincludedinthe
.
ReplaceSyntaxRule10)a)ii)with:
10) .
a) .
ii) LetARISETbethesetofaggregatingscontainedinRILandlet
NARIbethenumberofsuchsinARISET.GRISETandARISETshall
bedisjoint.
©ISO/IEC2026–Allrightsreserved
ISO/IEC 39075:2024/Cor.1:2026(en)
14.12
1. Rationale: Usecorrectsymbols.
ReplaceSyntaxRule12)a)iv)
12) .
a) .
ii) GROUP_BYis:
GROUP BY GEID , ., GEID
1 NUM_GE
2. Rationale: DeleteredundantConformanceRule.
DeleteConformanceRules3).
15 Procedurecalling
15.1 and
1. Rationale: Specifymissingdeclaredtype.
ReplaceSyntaxRule8)b)with:
8) .
b) IfPCistheIPCandIPChasadeclaredtypethatisabinding
tabletype,thenOTARTPCistherecordtypeofthedeclaredtypeofIPC.
2. Rationale: Correctasymboltopreventinnerqueriesfromexposingworkingrecordvariables.
ReplaceSyntaxRule9)with:
9) IREDTPCandOTARTPCshallbefieldname-disjoint.
16 Commonelements
16.8
1. Rationale: Definethenodeandedgetypelabels.
ReplaceSyntaxRule4)a)ii)with:
4) .
a) .
ii) IfGRVTisaclosedgraphreferencevaluetypewithconstrainingGQL-objecttype
COTthen:
©ISO/IEC2026–Allrightsreserved
ISOISO/IEC/IEC 3390759075:202:20244/C/Cor.or.1:21:202026(e6(enn))
1) IfLEissimplycontainedina,thenLEisanodelabel
expression.EverycontainedinLEshallidentifyanodetype
labelofCOT.
NOTE2—SeeSubclause18.1,“”,Syntax
Rule20.1)forthedefinitionofanodetypelabelofagraphtype.
2) Otherwise,LEisanedgelabelexpression.Everycontained
inLEshallidentifyanedgetypelabelofCOT.
NOTE3—SeeSubclause18.1,“”,Syntax
Rule20.2)forthedefinitionofanedgetypelabelofagraphtype.
2. Rationale: Specifycorrectvaluetype.
ReplaceSyntaxRule4)b)ii)with:
4) .
b) .
ii) IfthedeclaredtypeofEVRisaclosedgraphelementreferencevaluetypewith
constrainingGQL-objecttypeCOT,theneverycontainedinLE
shallidentifyalabelinthelabelsetofCOT.
17 Objectreferences
17.1 and
1. Rationale: CorrecttheapplicationofWG3:W22-051.
ReplacetheFormatofasfollows:
::=

[ { }. ] [ ]
18 Typeelements
18.1
1. Rationale: Definethenodeandedgetypelabels.
InsertthefollowingSyntaxRules:
20.1) AnodetypelabelofagraphtypeGTisanylabelfromtheunionofthenodetypelabelsetsof
allnodetypesofGT.
20.2) AnedgetypelabelofagraphtypeGTisanylabelfromtheunionoftheedgetypelabelsets
ofalledgetypesofGT.
©ISO/IEC2026–Allrightsreserved
ISO/IEC 39075:2024/Cor.1:2026(en)
18.2
1. Rationale: Supplymissingsubruleandcorrectsurroundingsubrules.
ReplaceSyntaxRule4)with:
4) ThelocalnodetypealiasofaANTSisdefinedasfollows.
Case:
a) IfANTSsimplycontainsaLNTA,thenthelocalnodetypealias
ofANTSisthenamespecifiedbythethatconstitutesLNTA.
b) IfANTSsimplycontainsaNTN,thenthelocalnodetypealiasof
ANTSisthenamespecifiedbythethatconstitutesNTN.
c) Otherwise,neithernorarespecifiedandthe
localnodetypealiasofANTSisthenameofanewsystem-generatedregularidentifier.
18.9
1. Rationale: Correctthesyntaxtoreflectthedefinedconcept.
Replacetheproductionfor
::=
{ }.
2. Rationale: CorrectthescopeoftheopenvaluetypeOVT.
ReplaceSyntaxRule89)d)with:
89) .
d) IfDUTincludesanopenvaluetypeOVT,thecomponenttypesofDVNF(DUT)shallnot
includeaproperclosedsubtypeofOVT.
3. Rationale: Bringtheverboseformsunderthesameconformanceastheshortforms.
ReplaceConformanceRules3),4),14),15),16),and17)asfollows:
3) WithoutFeatureGV18,“Smallsignedintegernumbers”,conformingGQLlanguageshallnot
containathatcontainsSMALLINTorSMALLINTEGER.
4) WithoutFeatureGV19,“Bigsignedintegernumbers”,conformingGQLlanguageshallnot
containathatcontainsBIGINTorBIGINTEGER.
14) WithoutFeatureGV05,“Smallunsignedintegernumbers”,conformingGQLlanguageshall
notcontainanthatcontainsUSMALLINTorUNSIGNED
SMALLINTEGER.
15) WithoutFeatureGV08,“Regularunsignedintegernumbers”,conformingGQLlanguageshall
notcontainanthatcontainsUINTorUNSIGNED
INTEGER.
©ISO/IEC2026–Allrightsreserved
ISO/IEC 39075:2024/Cor.1:2026(en)
16) WithoutFeatureGV10,“Bigunsignedintegernumbers”,conformingGQLlanguageshallnot
containanthatcontainsUBIGINTorUNSIGNEDBIG
INTEGER.
17) WithoutFeatureGV09,“Specifiedintegernumberprecision”,conformingGQLlanguageshall
notcontainanthatcontainsaora.
4. Rationale: CorrectthenameandscopeofaFeature.
ReplaceConformanceRule35)with:
35) WithoutFeatureGV39,“Temporaltypesupport”,conformingGQLlanguageshallnotcontain
a.
5. Rationale: AddmissingConformanceRule.
AddthefollowingConformanceRule:
40.1) WithoutFeatureGV51,“Specifiedlistmaximumlength”,conformingGQLlanguageshallnot
containathatcontains.
20 Valueexpressionsandspecifications
20.7
1. Rationale: InSubclause20.7,“”,SyntaxRule2)a)incorrectlyrestrictsvalidcombinations
inandduplicatesrestrictionsthatarespecifiedintheSubclausesofClause19,
“Predicates”.
DeleteSyntaxRule2)a)andreplaceSyntaxRule2)g)with:
2) .
g) TheSyntaxandConformanceRulesoftheSubclausesofClause19,“Predicates”,are
appliedtotheresultofthissyntactictransformation.
20.8
1. Rationale: Correctanincorrectexception.
ReplaceGeneralRule4)d)vi)1)with:
4) .
d) .
vi) .
1) IfNSisgreaterthanNT,thenanexceptionconditionisraised:data
exception—listdata,righttruncation(2
...