DbExpressionBuilder.GroupBy Method

Reference

Definition

Namespace:: System.Data.Common.CommandTrees.ExpressionBuilder

Assembly:: System.Data.Entity.dll

Important

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Creates a new DbGroupByExpression that groups the elements of the input set according to the specified group keys and applies the given aggregates.

public:
[System::Runtime::CompilerServices::Extension]
 static System::Data::Common::CommandTrees::DbGroupByExpression ^ GroupBy(System::Data::Common::CommandTrees::DbGroupExpressionBinding ^ input, System::Collections::Generic::IEnumerable<System::Collections::Generic::KeyValuePair<System::String ^, System::Data::Common::CommandTrees::DbExpression ^>> ^ keys, System::Collections::Generic::IEnumerable<System::Collections::Generic::KeyValuePair<System::String ^, System::Data::Common::CommandTrees::DbAggregate ^>> ^ aggregates);

public static System.Data.Common.CommandTrees.DbGroupByExpression GroupBy (this System.Data.Common.CommandTrees.DbGroupExpressionBinding input, System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<string,System.Data.Common.CommandTrees.DbExpression>> keys, System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<string,System.Data.Common.CommandTrees.DbAggregate>> aggregates);

static member GroupBy : System.Data.Common.CommandTrees.DbGroupExpressionBinding * seq<System.Collections.Generic.KeyValuePair<string, System.Data.Common.CommandTrees.DbExpression>> * seq<System.Collections.Generic.KeyValuePair<string, System.Data.Common.CommandTrees.DbAggregate>> -> System.Data.Common.CommandTrees.DbGroupByExpression

<Extension()>
Public Function GroupBy (input As DbGroupExpressionBinding, keys As IEnumerable(Of KeyValuePair(Of String, DbExpression)), aggregates As IEnumerable(Of KeyValuePair(Of String, DbAggregate))) As DbGroupByExpression

Parameters

input: DbGroupExpressionBinding

A DbGroupExpressionBinding that specifies the input set.

keys: IEnumerable<KeyValuePair<String,DbExpression>>

A list of string-expression pairs that define the grouping columns.

aggregates: IEnumerable<KeyValuePair<String,DbAggregate>>

A list of expressions that specify aggregates to apply.

Returns

DbGroupByExpression

A new DbGroupByExpression with the specified input set, grouping keys and aggregates.

Exceptions

ArgumentNullException

input, keys or aggregates is null, keys contains a null column key or expression, or aggregates contains a null aggregate column name or aggregate.

ArgumentException

Both keys and aggregates are empty, or an invalid or duplicate column name was specified.

Remarks

DbGroupByExpression allows either the list of keys or the list of aggregates to be empty, but not both.

Applies to

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