Join Methods (LINQ to Entities)

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The LINQ join methods are supported in LINQ to Entities, with the exception of those that accept an IEqualityComparer because the comparer cannot be translated to the data source. For more information, see Standard Query Operators in LINQ to Entities Queries. The following table lists the supported and unsupported join methods.

Supported and Unsupported Methods

Method Support Visual Basic function signature C# method signature

GroupJoin

Supported

 
Function GroupJoin(Of TOuter, TInner, TKey, TResult) ( _
outer As IQueryable(Of TOuter), _
inner As IEnumerable(Of TInner), _
outerKeySelector As Expression(Of Func(Of TOuter, TKey)), _
innerKeySelector As Expression(Of Func(Of TInner, TKey)), _
resultSelector As Expression(Of Func(Of TOuter, IEnumerable(Of TInner), TResult)) _
) As IQueryable(Of TResult)
 
IQueryable<TResult> GroupJoin<TOuter, TInner, TKey, TResult>(
this IQueryable<TOuter> outer,
IEnumerable<TInner> inner,
Expression<Func<TOuter, TKey>> outerKeySelector,
Expression<Func<TInner, TKey>> innerKeySelector,
Expression<Func<TOuter, IEnumerable<TInner>, TResult>> resultSelector
)

GroupJoin

Not Supported

 
Function GroupJoin(Of TOuter, TInner, TKey, TResult) ( _
outer As IQueryable(Of TOuter), _
inner As IEnumerable(Of TInner), _
outerKeySelector As Expression(Of Func(Of TOuter, TKey)), _
innerKeySelector As Expression(Of Func(Of TInner, TKey)), _
resultSelector As Expression(Of Func(Of TOuter, IEnumerable(Of TInner), TResult)), _
comparer As IEqualityComparer(Of TKey) _
) As IQueryable(Of TResult)
 
IQueryable<TResult> GroupJoin<TOuter, TInner, TKey, TResult>(
this IQueryable<TOuter> outer,
IEnumerable<TInner> inner,
Expression<Func<TOuter, TKey>> outerKeySelector,
Expression<Func<TInner, TKey>> innerKeySelector,
Expression<Func<TOuter, IEnumerable<TInner>, TResult>> resultSelector,
IEqualityComparer<TKey> comparer
)

Join

Supported

 
Function Join(Of TOuter, TInner, TKey, TResult) ( _
outer As IQueryable(Of TOuter), _
inner As IEnumerable(Of TInner), _
outerKeySelector As Expression(Of Func(Of TOuter, TKey)), _
innerKeySelector As Expression(Of Func(Of TInner, TKey)), _
resultSelector As Expression(Of Func(Of TOuter, TInner, TResult)) _
) As IQueryable(Of TResult)
 
IQueryable<TResult> Join<TOuter, TInner, TKey, TResult>(
this IQueryable<TOuter> outer,
IEnumerable<TInner> inner,
Expression<Func<TOuter, TKey>> outerKeySelector,
Expression<Func<TInner, TKey>> innerKeySelector,
Expression<Func<TOuter, TInner, TResult>> resultSelector
)

Join

Not Supported

 
 Function Join(Of TOuter, TInner, TKey, TResult) ( _
outer As IQueryable(Of TOuter), _
inner As IEnumerable(Of TInner), _
outerKeySelector As Expression(Of Func(Of TOuter, TKey)), _
innerKeySelector As Expression(Of Func(Of TInner, TKey)), _
resultSelector As Expression(Of Func(Of TOuter, TInner, TResult)), _
comparer As IEqualityComparer(Of TKey) _
) As IQueryable(Of TResult)
 
IQueryable<TResult> Join<TOuter, TInner, TKey, TResult>(
this IQueryable<TOuter> outer,
IEnumerable<TInner> inner,
Expression<Func<TOuter, TKey>> outerKeySelector,
Expression<Func<TInner, TKey>> innerKeySelector,
Expression<Func<TOuter, TInner, TResult>> resultSelector,
IEqualityComparer<TKey> comparer
)

See Also

Concepts

Supported and Unsupported Methods (LINQ to Entities)