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QueryExpressionRel

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__TOCDet/Assembly = ARCQuery
__TOCDet/Description = Enables 'jumping' or 'travelling' from a collection of one entity type to another (related) entity type.0x000D0x000A0x000D0x000AEnables queries like0x000D0x000A'Order/WHERE Amount 0x003E 10000 EUR/REL Customer/REL SupportTicket'0x000D0x000Awhich will show support tickets for all customer who at some time have ordered something for at least 10 000 EUR.0x000D0x000A0x000D0x000ACorresponds (very) coarsely to the JOIN concept in SQL0x000D0x000A0x000D0x000AThere are two ways for this to happen:0x000D0x000A0x000D0x000A1) -ToMany-:0x000D0x000AIf -IPRelationsKeysPointingTo- has a link for the current entity type, like 'Customer' having a link to 'Order' then a jump from a collection of Customers can be made to for instance an Order collection by iterating through all Orders with CustomerId present in the collection of Customers.0x000D0x000A0x000D0x000A2) -ToOne-:0x000D0x000AA jump from a collection of 'OrderLine' to 'Order', or 'Order' to 'Customer' can be made by iterating through the whole collection looking for respectively 'OrderId = xxx' and 'CustomerId = xxx' properties.0x000D0x000A0x000D0x000AVariant 1) (-ToMany-) will be the default attempted. If relevant relations for 1) is not found, then variant 2) (-ToOne-) will be attempted.0x000D0x000A0x000D0x000ADoes also work with -PKRelAttribute- (-ForeignEntity-).0x000D0x000A0x000D0x000ANOTE: The relevant keys for 'jumping' must exist. If you for instance do like this0x000D0x000ANOTE: (admittedly meaningless query, but it explains the point though):0x000D0x000ANOTE:   'Order/WHERE Amount 0x003E 10000 EUR/SELECT Amount, Created/REL Customer'0x000D0x000ANOTE: then the key CustomerId is not available, and the jumping breaks down.0x000D0x000ANOTE:   'Order/WHERE Amount 0x003E 10000 EUR/SELECT CustomerId, Amount, Created/REL Customer'0x000D0x000ANOTE: on the other hand would work (but use of SELECT is meaningless anyway of course).0x000D0x000A0x000D0x000ASee -SyntaxHelp-.
__TOCDet/DocFragType = Class
__TOCDet/Name = QueryExpressionRel
__TOCDet/Namespace = ARCQuery
__TOCDet/Type = QueryExpressionRel
__TOCDet/Attribute/AssemblyName = ARCQuery
__TOCDet/Attribute/BaseTypes = QueryExpression
__TOCDet/Attribute/ClassNamespace = ARCQuery
__TOCDet/Attribute/ClassType = QueryExpressionRel
__TOCDet/Attribute/Description = Enables 'jumping' or 'travelling' from a collection of one entity type to another (related) entity type.0x000D0x000A0x000D0x000AEnables queries like0x000D0x000A'Order/WHERE Amount 0x003E 10000 EUR/REL Customer/REL SupportTicket'0x000D0x000Awhich will show support tickets for all customer who at some time have ordered something for at least 10 000 EUR.0x000D0x000A0x000D0x000ACorresponds (very) coarsely to the JOIN concept in SQL0x000D0x000A0x000D0x000AThere are two ways for this to happen:0x000D0x000A0x000D0x000A1) -ToMany-:0x000D0x000AIf -IPRelationsKeysPointingTo- has a link for the current entity type, like 'Customer' having a link to 'Order' then a jump from a collection of Customers can be made to for instance an Order collection by iterating through all Orders with CustomerId present in the collection of Customers.0x000D0x000A0x000D0x000A2) -ToOne-:0x000D0x000AA jump from a collection of 'OrderLine' to 'Order', or 'Order' to 'Customer' can be made by iterating through the whole collection looking for respectively 'OrderId = xxx' and 'CustomerId = xxx' properties.0x000D0x000A0x000D0x000AVariant 1) (-ToMany-) will be the default attempted. If relevant relations for 1) is not found, then variant 2) (-ToOne-) will be attempted.0x000D0x000A0x000D0x000ADoes also work with -PKRelAttribute- (-ForeignEntity-).0x000D0x000A0x000D0x000ANOTE: The relevant keys for 'jumping' must exist. If you for instance do like this0x000D0x000ANOTE: (admittedly meaningless query, but it explains the point though):0x000D0x000ANOTE:   'Order/WHERE Amount 0x003E 10000 EUR/SELECT Amount, Created/REL Customer'0x000D0x000ANOTE: then the key CustomerId is not available, and the jumping breaks down.0x000D0x000ANOTE:   'Order/WHERE Amount 0x003E 10000 EUR/SELECT CustomerId, Amount, Created/REL Customer'0x000D0x000ANOTE: on the other hand would work (but use of SELECT is meaningless anyway of course).0x000D0x000A0x000D0x000ASee -SyntaxHelp-.
__TOCDet/Attribute/Interfaces = ITypeDescriber0x003BIEquatable0xoooo003CQueryExpression0xoooo003E
Execute/__TOCDet/Assembly = ARCQuery
Execute/__TOCDet/Description = Transforms the given input collection into a resulting collection.0x000D0x000A0x000D0x000AThe parameter data storage is used for sub classes implementing relations (transforming to collections of other types).0x000D0x000A0x000D0x000ATODO: Most probably we also need a parameter for what entity type the input collection represents TODO: (one might of course sample it, but the calling method should know anyway). 0x000D0x000ATODO: It is possible also that we need a parameter for current LinkContext, or OR TODO: rather, let parameter DataStorage just be the same where we find the key of the current entity type TODO: and assume that other entity collections are stored at the same level.0x000D0x000ATODO:0x000D0x000ATODO: SOLUTION: QueryCollection-class with all necessary parameters. This also enables0x000D0x000ATODO: method chaining (fluent interface) AND logging AND timing AND exception handling AND so on AND so on.0x000D0x000ATODO:0x000D0x000ATODO: Each Query-implementation adds an Extension method against QueryCollection.0x000D0x000ATODO: QueryCollection itself is IP, with keys for log-data and a Result-key.
Execute/__TOCDet/DocFragType = ClassMember
Execute/__TOCDet/IsInherited = False
Execute/__TOCDet/IsInheritedDoc = True
Execute/__TOCDet/Name = Execute
Execute/__TOCDet/Namespace = ARCQuery
Execute/__TOCDet/Type = QueryExpressionRel
Execute/__TOCDet/Attribute/DeclaringType = QueryExpression
Execute/__TOCDet/Attribute/Description = Transforms the given input collection into a resulting collection.0x000D0x000A0x000D0x000AThe parameter data storage is used for sub classes implementing relations (transforming to collections of other types).0x000D0x000A0x000D0x000ATODO: Most probably we also need a parameter for what entity type the input collection represents TODO: (one might of course sample it, but the calling method should know anyway). 0x000D0x000ATODO: It is possible also that we need a parameter for current LinkContext, or OR TODO: rather, let parameter DataStorage just be the same where we find the key of the current entity type TODO: and assume that other entity collections are stored at the same level.0x000D0x000ATODO:0x000D0x000ATODO: SOLUTION: QueryCollection-class with all necessary parameters. This also enables0x000D0x000ATODO: method chaining (fluent interface) AND logging AND timing AND exception handling AND so on AND so on.0x000D0x000ATODO:0x000D0x000ATODO: Each Query-implementation adds an Extension method against QueryCollection.0x000D0x000ATODO: QueryCollection itself is IP, with keys for log-data and a Result-key.
Execute/__TOCDet/Attribute/MethodName = Execute
Execute/__TOCDet/Attribute/MethodSignature = ARCQuery.QueryExpressionWithSuggestions Execute(ARCQuery.Query)
StrType/__TOCDet/Assembly = ARCQuery
StrType/__TOCDet/Description = In the simplest terms, the -ToStringVeryShort- representation of the type that we are 'jumping' to.0x000D0x000A0x000D0x000AA more exact explanation is that this is either -EntityTypeAndKey-.-OppositeTerm- (Variant 1, -ToMany-) or -KeyWithoutId-.0x000D0x000A(Variant 2, -ToOne-).0x000D0x000ATODO: Clarify this / explain in more formal terms.
StrType/__TOCDet/DocFragType = ClassMember
StrType/__TOCDet/IsInherited = False
StrType/__TOCDet/IsInheritedDoc = False
StrType/__TOCDet/Lines = 5
StrType/__TOCDet/Name = StrType
StrType/__TOCDet/Namespace = ARCQuery
StrType/__TOCDet/Type = QueryExpressionRel
StrType/__TOCDet/Attribute/DeclaringType = QueryExpressionRel
StrType/__TOCDet/Attribute/Description = In the simplest terms, the -ToStringVeryShort- representation of the type that we are 'jumping' to.0x000D0x000A0x000D0x000AA more exact explanation is that this is either -EntityTypeAndKey-.-OppositeTerm- (Variant 1, -ToMany-) or -KeyWithoutId-.0x000D0x000A(Variant 2, -ToOne-).0x000D0x000ATODO: Clarify this / explain in more formal terms.
StrType/__TOCDet/Attribute/MethodName = StrType
StrType/__TOCDet/Attribute/MethodSignature = System.String StrType
SyntaxHelp/__TOCDet/Assembly = ARCQuery
SyntaxHelp/__TOCDet/Description = 'REL 0x007Btype0x007D'0x000D0x000AExamples:0x000D0x000A'REL Customer',0x000D0x000A'REL Order'0x000D0x000A
SyntaxHelp/__TOCDet/DocFragType = ClassMember
SyntaxHelp/__TOCDet/IsInherited = False
SyntaxHelp/__TOCDet/IsInheritedDoc = False
SyntaxHelp/__TOCDet/Lines = 5
SyntaxHelp/__TOCDet/Name = SyntaxHelp
SyntaxHelp/__TOCDet/Namespace = ARCQuery
SyntaxHelp/__TOCDet/Type = QueryExpressionRel
SyntaxHelp/__TOCDet/Attribute/DeclaringType = QueryExpressionRel
SyntaxHelp/__TOCDet/Attribute/Description = 'REL 0x007Btype0x007D'0x000D0x000AExamples:0x000D0x000A'REL Customer',0x000D0x000A'REL Order'0x000D0x000A
SyntaxHelp/__TOCDet/Attribute/MethodName = SyntaxHelp
SyntaxHelp/__TOCDet/Attribute/MethodSignature = System.String SyntaxHelp
TryCheckForExistenceOfKey/__TOCDet/Assembly = ARCQuery
TryCheckForExistenceOfKey/__TOCDet/Description = Used by query expressions in order to catch wrong field names used or misspelling of field names.0x000D0x000A0x000D0x000AReturns TRUE if either:0x000D0x000A1) -TryGetFromTypeAndFieldName succeeds (in which case out parameter keyAsPK will be set),0x000D0x000A2) (new from Jan 2022) -AllEntityMethodKeysForEntityTypeDict contains the key,0x000D0x000A3) -CurrentStrictness- = OFF,0x000D0x000A4) -Result- is empty, or,0x000D0x000A5) At least one element in -Result- contains the given key0x000D0x000A0x000D0x000ANote that this check must be deferred to the actual execution of the query, not at -TryParse-, because the query expression mechanism has no concept of for which entity types it operates on.0x000D0x000A0x000D0x000AWill call -ShouldTerminate- if fails to get the key, this again will set -TerminateReason- with detailed information about available keys (that is, with a helpful error message).
TryCheckForExistenceOfKey/__TOCDet/DocFragType = ClassMember
TryCheckForExistenceOfKey/__TOCDet/IsInherited = True
TryCheckForExistenceOfKey/__TOCDet/IsInheritedDoc = True
TryCheckForExistenceOfKey/__TOCDet/Name = TryCheckForExistenceOfKey
TryCheckForExistenceOfKey/__TOCDet/Namespace = ARCQuery
TryCheckForExistenceOfKey/__TOCDet/Type = QueryExpressionRel
TryCheckForExistenceOfKey/__TOCDet/Attribute/DeclaringType = QueryExpression
TryCheckForExistenceOfKey/__TOCDet/Attribute/Description = Used by query expressions in order to catch wrong field names used or misspelling of field names.0x000D0x000A0x000D0x000AReturns TRUE if either:0x000D0x000A1) -TryGetFromTypeAndFieldName succeeds (in which case out parameter keyAsPK will be set),0x000D0x000A2) (new from Jan 2022) -AllEntityMethodKeysForEntityTypeDict contains the key,0x000D0x000A3) -CurrentStrictness- = OFF,0x000D0x000A4) -Result- is empty, or,0x000D0x000A5) At least one element in -Result- contains the given key0x000D0x000A0x000D0x000ANote that this check must be deferred to the actual execution of the query, not at -TryParse-, because the query expression mechanism has no concept of for which entity types it operates on.0x000D0x000A0x000D0x000AWill call -ShouldTerminate- if fails to get the key, this again will set -TerminateReason- with detailed information about available keys (that is, with a helpful error message).
TryCheckForExistenceOfKey/__TOCDet/Attribute/MethodName = TryCheckForExistenceOfKey
TryCheckForExistenceOfKey/__TOCDet/Attribute/MethodSignature = Boolean TryCheckForExistenceOfKey(ARCQuery.Query, ARCCore.IK, ARCCore.PK ByRef)

Edit single sub keys only: __TOCDet / Execute / StrType / SyntaxHelp / TryCheckForExistenceOfKey

Generated 2025-06-19 02:58:48.924 UTC