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

ISO/IEC 39075:2024/Cor 1:2026 is an ISO and IEC technical corrigendum to ISO/IEC 39075:2024 for GQL, the database language for graph queries. It corrects selected rules in the language definition, including catalog structure, execution outcomes, session commands, query syntax, type rules, literals, and conformance. Readers use it to update implementations and conformance checks for GQL.

What does ISO/IEC 39075:2024/Cor 1:2026 specify?

ISO/IEC 39075:2024/Cor 1:2026 specifies corrections to the first edition of the GQL standard. Its changes are grouped by clause, mainly in Clause 4 Concepts, Clause 7 Session management, Clauses 14 to 22 on statements, expressions, types, and lexical elements, and Clause 24 Conformance.

The document also updates Figure 2 and Table 10. In practice, that means the corrigendum is used alongside ISO/IEC 39075:2024 to apply the corrected language rules and feature relationships.

What are the key requirements of ISO/IEC 39075:2024/Cor 1:2026?

ISO/IEC 39075:2024/Cor 1:2026 mainly tightens the GQL rules that implementations use for catalog contents, feature-dependent syntax, type consistency, and error handling. The practical effect is to align implementations, parsers, and conformance tests with the corrected language definition.

Catalog, schema, and execution rules

• Clause 4.2.5.1 replaces Figure 2 so the GQL-catalog model matches the normative text. The corrected figure shows the catalog root, the possible GQL-directory or GQL-schema base, and the primary and secondary catalog objects. For implementers, this is a model alignment issue: catalog software should follow the corrected structure.
• Clause 4.2.5.3 adds a rule for GQL-schemas created by an implementation. A GQL-implementation may auto-populate a GQL-schema in an implementation-defined way, but without Feature GC00, it shall not provide a GQL-schema with a pre-populated graph. This matters when a system creates default catalog content.
• Clause 4.8.4 says a failed outcome records an exception condition, and whether it returns a partial result is implementation-dependent. In practice, users and test tools must not assume that a failed execution returns nothing.

Session management and optional commands

• Clause 7 adds and corrects conformance rules for session commands. Without Feature GS09, GS17, GS08, GS16, or GS18, a conforming GQL language shall not include the corresponding session set, reset, or close constructs. This tells implementers which session clauses are optional features rather than always-available syntax.
• Clause 7.2 and 7.3 clarify what can appear in SESSIONRESET and SESSIONCLOSE related syntax. For buyers and reviewers, these feature gates are important because they determine which session controls an engine actually supports.

Query, procedure, and expression rules

• Clause 14.7 corrects the rules so a binding variable is not referenced from another on the right-hand side in the same statement. It also makes optional through Feature GP05. This prevents invalid self-references and affects how query authors write LET blocks.
• Clause 14.10 and 14.11 tighten and . The text restricts when aggregate functions may appear in sort keys and requires the alias sets GRISET and ARISET to be disjoint. This matters for query correctness, especially in grouped and aggregated results.
• Clause 15.1 corrects and . A declared binding table type now maps to the record type of the declared type for an inline procedure call, and the related field names must be disjoint. That is important for procedure interfaces and name collision checks.

Types, labels, literals, and conformance

• Clause 4.13.2 and Clause 18 define node type labels and edge type labels, and Clause 4.13.2.5 states when a property P is of a property type PT. Clause 4.13.2.7 and Clause 22.17 also correct graph-type-specific property value type combination rules. These rules support structural consistency in graph models and type checking in implementations.
• Clause 18.9 updates rules, including feature gates for signed and unsigned integer forms, temporal types, and list maximum length. Clause 21.2 and 21.3 correct literal and token rules, including byte string literals, temporal literals, and the reserved word TYPE. This affects both parsers and schema/type validators.
• Clause 24 revises minimum conformance and implied feature relationships. A claim of conformance must cover at least Feature GC00 or GC04, and Table 10 is updated with additional and removed feature relationships. For certification and vendor declarations, this is the section that determines the required feature baseline.

What terms does ISO/IEC 39075:2024/Cor 1:2026 define?

ISO/IEC 39075:2024/Cor 1:2026 uses several GQL-specific terms that matter for implementation and testing.

• GQL-catalog - the catalog structure whose root is one instance of either GQL-directory or GQL-schema, holding primary and secondary catalog objects.
• GQL-schema - the schema object that may be automatically populated when created, depending on implementation behavior and Feature GC00.
• failed outcome - an execution outcome that records an exception condition, with partial results allowed only as implementation-dependent behavior.
• node type label - any label contained in the node type label set of at least one node type of a graph type.
• edge type label - any label contained in the edge type label set of at least one edge type of a graph type.
• property type - a property P is of a property type PT when they have equal names and P’s value is of PT’s value type.
• GRISET - the set of aliases contained in the grouping clause, used in the return statement rules.
• ARISET - the set of aliases for aggregating return items that are not in GRISET.

Who uses ISO/IEC 39075:2024/Cor 1:2026?

ISO/IEC 39075:2024/Cor 1:2026 is used by people who build, test, or evaluate GQL support in graph database and data management products. Implementers use it to correct parsers, execution engines, catalog handling, session commands, type checking, and error reporting.

It is also relevant to quality managers, conformance testers, and buyers who need to check whether a GQL implementation supports particular features such as GC00, GS09, GP05, or GV39. In practice, these readers use the corrigendum to verify feature declarations, test cases, and product documentation.

What changed in ISO/IEC 39075:2024/Cor 1:2026 from the previous edition?

ISO/IEC 39075:2024/Cor 1:2026 corrects ISO/IEC 39075:2024 by replacing Figure 2, adding and revising conformance rules, and fixing syntax and semantic rules across the language. The corrections cover GQL-catalog and GQL-schema behavior, failed outcomes, node and edge type labels, property types, session commands, LET and RETURN processing, procedure calls, label expressions, object references, value types, literals, and conformance feature relationships.

Which standards are used with ISO/IEC 39075:2024/Cor 1:2026?

• ISO/IEC 39075:2024 - the base GQL standard that this technical corrigendum corrects and updates.

What does the ISO/IEC 39075:2024/Cor 1:2026 document contain?

ISO/IEC 39075:2024/Cor 1:2026 contains clause-by-clause corrections rather than a full restatement of GQL. It replaces Figure 2, revises Table 10 on implied feature relationships, and updates syntax rules, general rules, and conformance rules in the affected clauses.

The document is useful for implementation work because it changes how parsers, validators, and execution engines should treat session commands, type names, literals, aggregate and list functions, and exception conditions. It also corrects the feature dependencies that support minimum conformance declarations.

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
...