ISO/IEC 9075-2:2023

INTERNATIONAL ISO/IEC
STANDARD 9075-2
Sixth edition
2023-06
Information technology — Database
languages SQL —
Part 2:
Foundation (SQL/Foundation)
Technologies de l'information — Langages de base de données SQL —
Partie 2: Fondations (SQL/Fondations)
Reference number
© ISO/IEC 2023
© ISO/IEC 2023
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Published in Switzerland
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© ISO/IEC 2023 – All rights reserved

ISO/IEC9075-2:2023(E)
Contents Page
Foreword.xix
Introduction.xxi
1 Scope.1
2 Normativereferences.2
3 Termsanddefinitions.4
3.1 DefinitionstakenfromISO/IEC10646:2020.4
3.2 DefinitionstakenfromISO/IEC14651:2020.5
3.3 DefinitionstakenfromISO8601-1:2019.5
3.4 DefinitionstakenfromXQueryandXPathFunctionsandOperators3.1.7
3.5 Definitionsprovidedinthisdocument.7
4 Concepts.15
4.1 Notationsandconventions.15
4.1.1 Notations.15
4.1.2 Useofterms.15
4.2 Data types.16
4.2.1 Generalintroductiontodatatypes.16
4.2.2 Namingofpredefinedtypes.17
4.2.3 Hostlanguagedatatypes.18
4.2.4 Datatypeterminology.18
4.2.5 Propertiesofdistinct.20
4.3 Characterstrings.21
4.3.1 Introductiontocharacterstrings.21
4.3.2 Comparisonofcharacterstrings.21
4.3.3 Operationsinvolvingcharacterstrings.22
4.3.3.1 Regularexpressionsyntaxes.22
4.3.3.2 Operatorsthatoperateoncharacterstringsandreturncharacterstrings.22
4.3.3.3 Otheroperatorsinvolvingcharacterstrings.25
4.3.3.4 Operationsinvolvinglargeobjectcharacterstrings.26
4.3.4 Characterrepertoires.27
4.3.5 Characterencodingforms.28
4.3.6 Collations.28
4.3.7 Character sets.29
4.3.8 Universalcharactersets.31
4.4 Binary strings.31
4.4.1 Introductiontobinarystrings.31
4.4.2 Binarystringcomparison.31
4.4.3 Operationsinvolvingbinarystrings.31
4.4.3.1 Operatorsthatoperateonbinarystringsandreturnbinarystrings.31
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ISO/IEC9075-2:2023(E)
4.4.3.2 Otheroperatorsinvolvingbinarystrings.32
4.5 Numbers.32
4.5.1 Introductiontonumbers.32
4.5.2 Characteristicsofnumbers.33
4.5.3 Operationsinvolvingnumbers.34
4.6 Boolean types.35
4.6.1 IntroductiontoBooleantypes.35
4.6.2 ComparisonandassignmentofBooleans.36
4.6.3 OperationsinvolvingBooleans.36
4.6.3.1 OperationsonBooleansthatreturnBooleans.36
4.6.3.2 OtheroperatorsinvolvingBooleans.36
4.7 Datetimesandintervals.36
4.7.1 Introductiontodatetimesandintervals.36
4.7.2 Datetimes.37
4.7.3 Intervals.39
4.7.4 Operationsinvolvingdatetimesandintervals.41
4.8 JSONtypes.41
4.8.1 IntroductiontoJSONtypes.41
4.8.2 ComparisonandassignmentofJSONvalues.42
4.8.3 OperationsinvolvingJSONvalues.43
4.9 User-defined types.43
4.9.1 Introductiontouser-definedtypes.43
4.9.2 Distincttypes.44
4.9.3 Structured types.44
4.9.3.1 Introductiontostructuredtypes.44
4.9.3.2 Observerfunctionsandmutatorfunctions.44
4.9.3.3 Constructors.44
4.9.3.4 Subtypesandsupertypes.45
4.9.4 Methods.46
4.9.5 User-definedtypecomparisonandassignment.47
4.9.6 Transformsforuser-definedtypes.48
4.9.7 User-definedtypedescriptor.48
4.10 Row types.50
4.11 Referencetypes.50
4.11.1 Introductiontoreferencetypes.50
4.11.2 Operationsinvolvingreferences.51
4.12 Collectiontypes.51
4.12.1 Introductiontocollectiontypes.51
4.12.2 Arrays.52
4.12.3 Multisets.52
4.12.4 Collectioncomparisonandassignment.52
4.12.5 Operationsinvolvingarrays.53
4.12.5.1 Operatorsthatoperateonarrayvaluesandreturnarrayelements.53
4.12.5.2 Operatorsthatoperateonarrayvaluesandreturnarrayvalues.53
4.12.5.3 Operatorsthatoperateonarrayvaluesandreturnnumbers.53
4.12.6 Operationsinvolvingmultisets.53
4.12.6.1 Operatorsthatoperateonmultisetsandreturnmultisetelements.53
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ISO/IEC9075-2:2023(E)
4.12.6.2 Operatorsthatoperateonmultisetsandreturnmultisets.53
4.12.6.3 Operatorsthatoperateonmultisetvaluesandreturnnumbers.54
4.13 Dataconversions.54
4.14 Domains.55
4.15 Columns,fields,andattributes.55
4.16 Periods.57
4.16.1 Introductiontoperiods.57
4.16.2 Operationsinvolvingperiods.58
4.17 Tables.58
4.17.1 Introductiontotables.58
4.17.2 Basetables.58
4.17.2.1 Introductiontobasetables.58
4.17.2.2 Regularpersistentbasetables.59
4.17.2.3 System-versioned tables.59
4.17.2.4 Temporary tables.59
4.17.3 Derivedtables.60
4.17.4 Transienttables.61
4.17.5 Uniqueidentificationoftables.61
4.17.6 Tableupdatability.61
4.17.7 Table descriptors.62
4.17.8 Syntacticanalysisofderivedtablesandcursors.63
4.17.9 Referenceabletables,subtables,andsupertables.65
4.17.10 Operationsinvolvingtables.66
4.17.11 Rangevariables.69
4.17.12 Identitycolumns.70
4.17.13 Basecolumnsandgeneratedcolumns.70
4.17.14 Grouped tables.70
4.17.15 Windowed tables.71
4.18 Dataanalysisoperations.72
4.18.1 Introductiontodataanalysisoperations.72
4.18.2 Groupfunctions.72
4.18.3 Windowfunctions.73
4.18.4 Aggregate functions.75
4.18.5 Rowpatternmeasures.77
4.19 Rowpatternmatching.78
4.19.1 Introductiontorowpatternmatching.78
4.19.2 Matchingrowswithapattern.78
4.19.3 Rowpatternmatchingillustrated.79
4.19.4 Rowpatternpartitioning.83
4.19.5 Rowordering.83
4.19.6 Rowpatternmeasurecolumns.83
4.19.7 Numberofrowspermatch.83
4.19.8 Skippingrowsaftermatching.84
4.20 Rowpatterns.84
4.21 Unionsofrowpatternvariables.85
4.22 DefiningBooleanconditions.85
4.23 Scalarexpressionsinrowpatternmatching.86
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ISO/IEC9075-2:2023(E)
4.23.1 Introductiontoscalarsinrowpatternmatching.86
4.23.2 Runningvs.finalsemantics.86
4.23.3 Rowpatternnavigationoperations.87
4.23.4 Rowpatternclassifierfunction.87
4.23.5 Rowpatternmatchnumberfunction.87
4.24 Determinism.87
4.25 Integrityconstraints.88
4.25.1 Overviewofintegrityconstraints.88
4.25.2 Checkingofconstraints.88
4.25.3 Tableconstraints.
...