/ doc / toc / ARCQuery / Class / FunctionKey / __TOCDet / Description

Description

Edit keys at this level only

= Extracts data from an already existing value like extracting Year from a DateTime in 'Created.Year()'.0x000D0x000A0x000D0x000AThis is an expandable concept, that is, you can create your own implementations of this class in your -ApplicationSpecificCode-.0x000D0x000A0x000D0x000AOften the extraction is actually a simplification of the existing value, like Created.Year() which would for '2020-06-11 13:36' return '2020'.0x000D0x000A0x000D0x000AImplementing classes in -StandardAgoRapideCode-, more specific -ARCQuery-, are:0x000D0x000A-FunctionKeyAbs-0x000D0x000A-FunctionKeyDate-0x000D0x000A-FunctionKeyDayOfWeek-0x000D0x000A-FunctionKeyDouble-0x000D0x000A-FunctionKeyFirstLine-0x000D0x000A-FunctionKeyHourMinute-0x000D0x000A-FunctionKeyInt-0x000D0x000A-FunctionKeyLength-0x000D0x000A-FunctionKeyMonth-0x000D0x000A-FunctionKeyQuarter-0x000D0x000A-FunctionKeyShort-0x000D0x000A-FunctionKeyTMB-0x000D0x000A-FunctionKeyTotalHours-0x000D0x000A-FunctionKeyTotalMinutes-0x000D0x000A-FunctionKeyType-0x000D0x000A-FunctionKeyVeryShort-0x000D0x000A-FunctionKeyWeek-0x000D0x000A-FunctionKeyYear-0x000D0x000A-FunctionKeyYearMonth-0x000D0x000A-FunctionKeyYearQuarter-0x000D0x000A-FunctionKeyYearWeek-0x000D0x000A(these are stored in -CompoundKey- as -FunctionKeys-.)0x000D0x000A0x000D0x000Aand also (see -FunctionKeyAggregate-):0x000D0x000A-FunctionKeyAggregateAvg-0x000D0x000A-FunctionKeyAggregateCount-0x000D0x000A-FunctionKeyAggregateDistinct-0x000D0x000A-FunctionKeyAggregateJoin-0x000D0x000A-FunctionKeyAggregateMax-0x000D0x000A-FunctionKeyAggregateMin-0x000D0x000A-FunctionKeyAggregateSingle-0x000D0x000A-FunctionKeyAggregateSum-0x000D0x000A(these are stored in -ForeignKey- as -AggregateKeys-.)0x000D0x000A0x000D0x000ATODO: Add a -PK- field, describing the value that is returned.0x000D0x000A0x000D0x000AIt can also be said to work as a function against a value field, but with the syntax 'value.functionName()' instead of functionName(value).0x000D0x000A0x000D0x000A(See also -ValueComparer- which can evaluate expressions like 'WHERE Created = ThisYear')0x000D0x000A0x000D0x000AExplanation of the conceptual difference between -ValueComparer- and -FunctionKey-:0x000D0x000AThese two concepts are working from two different 'origins'.0x000D0x000A-FunctionKey- is necessary if you want to pivot around the value (for instance with -QueryExpressionPivot-).0x000D0x000A-ValueComparer- is more practical if the value can have different interpretations at the same time.0x000D0x000AAn example is -ValueComparerDateTime- which understands that 'Created' can be all of 'ThisYear', 'ThisMonth', 'ThisWeek', 'InTheMorning', 'ThisMorning' and so on.0x000D0x000A(It would be time consuming to write all the necessary -FunctionKey- implementations in order to support this. and the query syntax would be more verbose ('Created.YearNumber = ThisYear' or something similar, instead of just 'Created = ThisYear').)0x000D0x000A0x000D0x000ANote that the concept is inherently expandable, you can create your own sub-classes and integrate them with -StandardAgoRapideCode-.0x000D0x000A0x000D0x000ANote how any -ApplicationSpecificCode- implementations must be added to -Parsers- at application startup in order for them to be recognized by -TryParse-.

Edit keys at all sub levels.
NOTE: Edits are always additive. Use 'Invalid' in order to delete keys.

Generated 2025-06-19 08:45:03.395 UTC