AggregateFluentBase<TResult>.Lookup<TForeignDocument, TAsElement, TAs, TNewResult> Method (IMongoCollection<TForeignDocument>, BsonDocument, PipelineDefinition<TForeignDocument, TAsElement>, FieldDefinition<TNewResult, TAs>, AggregateLookupOptions<TForeignDocument, TNewResult>)

Appends a lookup stage to the pipeline.

Namespace: MongoDB.Driver
Assembly: MongoDB.Driver (in MongoDB.Driver.dll) Version: 2.17.0+b316340e6cc3a8bfc8638dc31b54fbbfe41bfcb2

Syntax

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public virtual IAggregateFluent<TNewResult> Lookup<TForeignDocument, TAsElement, TAs, TNewResult>(
	IMongoCollection<TForeignDocument> foreignCollection,
	BsonDocument let,
	PipelineDefinition<TForeignDocument, TAsElement> lookupPipeline,
	FieldDefinition<TNewResult, TAs> as,
	AggregateLookupOptions<TForeignDocument, TNewResult> options = null
)
where TAs : Object, IEnumerable<TAsElement>

Public Overridable Function Lookup(Of TForeignDocument, TAsElement, TAs As {Object, IEnumerable(Of TAsElement)}, TNewResult) ( 
	foreignCollection As IMongoCollection(Of TForeignDocument),
	let As BsonDocument,
	lookupPipeline As PipelineDefinition(Of TForeignDocument, TAsElement),
	as As FieldDefinition(Of TNewResult, TAs),
	Optional options As AggregateLookupOptions(Of TForeignDocument, TNewResult) = Nothing
) As IAggregateFluent(Of TNewResult)

abstract Lookup : 
        foreignCollection : IMongoCollection<'TForeignDocument> * 
        let : BsonDocument * 
        lookupPipeline : PipelineDefinition<'TForeignDocument, 'TAsElement> * 
        as : FieldDefinition<'TNewResult, 'TAs> * 
        ?options : AggregateLookupOptions<'TForeignDocument, 'TNewResult> 
(* Defaults:
        let _options = defaultArg options null
*)
-> IAggregateFluent<'TNewResult>  when 'TAs : Object and IEnumerable<'TAsElement>
override Lookup : 
        foreignCollection : IMongoCollection<'TForeignDocument> * 
        let : BsonDocument * 
        lookupPipeline : PipelineDefinition<'TForeignDocument, 'TAsElement> * 
        as : FieldDefinition<'TNewResult, 'TAs> * 
        ?options : AggregateLookupOptions<'TForeignDocument, 'TNewResult> 
(* Defaults:
        let _options = defaultArg options null
*)
-> IAggregateFluent<'TNewResult>  when 'TAs : Object and IEnumerable<'TAsElement>

Parameters

foreignCollection: Type: MongoDB.Driver.IMongoCollection<TForeignDocument>
The foreign collection.
let: Type: MongoDB.Bson.BsonDocument
The "let" definition.
lookupPipeline: Type: MongoDB.Driver.PipelineDefinition<TForeignDocument, TAsElement>
The lookup pipeline.
as: Type: MongoDB.Driver.FieldDefinition<TNewResult, TAs>
The as field in TNewResult in which to place the results of the lookup pipeline.
options (Optional): Type: MongoDB.Driver.AggregateLookupOptions<TForeignDocument, TNewResult>
The options.

Type Parameters

TForeignDocument: The type of the foreign collection documents.
TAsElement: The type of the as field elements.
TAs: The type of the as field.
TNewResult: The type of the new result.

Return Value

Type: IAggregateFluent<TNewResult>
The fluent aggregate interface.

Implements

IAggregateFluent<TResult>.Lookup<TForeignDocument, TAsElement, TAs, TNewResult>(IMongoCollection<TForeignDocument>, BsonDocument, PipelineDefinition<TForeignDocument, TAsElement>, FieldDefinition<TNewResult, TAs>, AggregateLookupOptions<TForeignDocument, TNewResult>)

Reference

AggregateFluentBase<TResult> Class

Lookup Overload

MongoDB.Driver Namespace