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QueryExpressionSelect

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__TOCDet/Assembly = ARCQuery
__TOCDet/Description = Selects which fields to include.0x000D0x000A0x000D0x000ANote: -QueryExpressionAll- differs from -QueryExpressionSelect- 'SELECT *' regarding use of -EntityMethodKey-s.0x000D0x000AThe query 'Customer/All' will not include -EntityMethodKey-s, while 'Customer/SELECT *' would.0x000D0x000A0x000D0x000A'SELECT *' can be used in connection with -CompoundKey-, like for instance0x000D0x000A'Customer/SELECT *, CountP()' which will select all fields in addition to a new field calculated by -NewKeyCountP-.0x000D0x000ASee -CompoundKey- for the quite rich functionality offered (like traversion of entity relations for instance).0x000D0x000A0x000D0x000AHINT: It is recommended to use 'AS' when using -CompoundKey- if subsequent -QueryExpression-s follows.0x000D0x000AHINT: This will reduce parsing complexities because a complex field name may be unnecessary attempted evaluated as a -CompoundKey-.0x000D0x000AHINT: Example: For 'Customer/SELECT Name, Order.OrderLine.Sum.Sum()/ORDER BY Order.OrderLine.Sum.Sum()', HINT: if the key 'Order.OrderLine.Sum.Sum()' does not exist for some Customer, it will be attempted reevaluated by the following -QueryExpressionOrderBy-0x000D0x000AHINT: and may be misunderstood.0x000D0x000AHINT: Doing instead 'Customer/SELECT Name, Order.OrderLine.Sum.Sum() AS OrderSum/ORDER BY OrderSum' will remove this possibility0x000D0x000AHINT: (and be more readable also).0x000D0x000A0x000D0x000ANote: The original key type is not necessarily preserved.0x000D0x000ASee hack in -OrderAndReconstructKeys- (called from -ToHTMLSimpleSingle- for details.0x000D0x000A0x000D0x000ATODO: Add some functionality recognizing -PriorityOrder-, like0x000D0x000ATODO: 'SELECT' which could select only from -Important- or lesser value.0x000D0x000ATODO: Or 'SELECT WHERE PriorityOrder LEQ Important' (Using negative values for PriorityOrder is not very intuitive here).0x000D0x000ATODO: or any other query against the property keys for the relevant entity class.0x000D0x000A0x000D0x000ASee -SyntaxHelp-.
__TOCDet/DocFragType = Class
__TOCDet/Name = QueryExpressionSelect
__TOCDet/Namespace = ARCQuery
__TOCDet/Type = QueryExpressionSelect
__TOCDet/Attribute/AssemblyName = ARCQuery
__TOCDet/Attribute/BaseTypes = QueryExpression
__TOCDet/Attribute/ClassNamespace = ARCQuery
__TOCDet/Attribute/ClassType = QueryExpressionSelect
__TOCDet/Attribute/Description = Selects which fields to include.0x000D0x000A0x000D0x000ANote: -QueryExpressionAll- differs from -QueryExpressionSelect- 'SELECT *' regarding use of -EntityMethodKey-s.0x000D0x000AThe query 'Customer/All' will not include -EntityMethodKey-s, while 'Customer/SELECT *' would.0x000D0x000A0x000D0x000A'SELECT *' can be used in connection with -CompoundKey-, like for instance0x000D0x000A'Customer/SELECT *, CountP()' which will select all fields in addition to a new field calculated by -NewKeyCountP-.0x000D0x000ASee -CompoundKey- for the quite rich functionality offered (like traversion of entity relations for instance).0x000D0x000A0x000D0x000AHINT: It is recommended to use 'AS' when using -CompoundKey- if subsequent -QueryExpression-s follows.0x000D0x000AHINT: This will reduce parsing complexities because a complex field name may be unnecessary attempted evaluated as a -CompoundKey-.0x000D0x000AHINT: Example: For 'Customer/SELECT Name, Order.OrderLine.Sum.Sum()/ORDER BY Order.OrderLine.Sum.Sum()', HINT: if the key 'Order.OrderLine.Sum.Sum()' does not exist for some Customer, it will be attempted reevaluated by the following -QueryExpressionOrderBy-0x000D0x000AHINT: and may be misunderstood.0x000D0x000AHINT: Doing instead 'Customer/SELECT Name, Order.OrderLine.Sum.Sum() AS OrderSum/ORDER BY OrderSum' will remove this possibility0x000D0x000AHINT: (and be more readable also).0x000D0x000A0x000D0x000ANote: The original key type is not necessarily preserved.0x000D0x000ASee hack in -OrderAndReconstructKeys- (called from -ToHTMLSimpleSingle- for details.0x000D0x000A0x000D0x000ATODO: Add some functionality recognizing -PriorityOrder-, like0x000D0x000ATODO: 'SELECT' which could select only from -Important- or lesser value.0x000D0x000ATODO: Or 'SELECT WHERE PriorityOrder LEQ Important' (Using negative values for PriorityOrder is not very intuitive here).0x000D0x000ATODO: or any other query against the property keys for the relevant entity class.0x000D0x000A0x000D0x000ASee -SyntaxHelp-.
__TOCDet/Attribute/Interfaces = ITypeDescriber0x003BIEquatable0xoooo003CQueryExpression0xoooo003E

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Generated 2024-07-03 12:32:59.680 UTC