DataSource for Entity Framework in WPF
DataSource for Entity Framework in WPF / Programming Guide / Query Operators Supported in Live Views
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    Query Operators Supported in Live Views
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    LiveLinq supports all LINQ query operators in its queries. Not all operators have LiveLinq-specific implementation benefiting from indexes and other query execution optimization techniques, but such operations simply use the standard LINQ to Objects (or LINQ to XML) implementations, so it is transparent to the user.

    However, not all query operations can be used in live views. This is because not all query operations have incremental view maintenance algorithms, as some would require re-populating from scratch (requerying) every time they are maintained. If your query contains such operations, you won't be able to use that query to create a live view. An attempt to do that will cause a compilation error.

    Here is the list of query operators allowed in live views:

     

    Operator

    Notes

    Select

    Overload with selector depending on the index is not allowed.

    Where

    Overload with predicate depending on the index is not allowed.

    Join

    Overload with comparer is not allowed.

    GroupJoin

    Overload with comparer is not allowed.

    OrderBy

    Overload with comparer is not allowed.

    OrderByDescending

    Overload with comparer is not allowed.

    GroupBy

    Overload with comparer is not allowed.

    SelectMany

    Overloads with selector and collectionSelector depending on the index are not allowed.

    Union

     

    Concat

     

    Aggregate

    Use LiveAggregate method if you want to optimize performance with incremental view maintenance.

    Count

    Use LiveCount method if you want to optimize performance with incremental view maintenance.

    Min/Max

    Use LiveMin/LiveMax methods if you want to optimize performance with incremental view maintenance.

    Sum

    Use LiveSum method if you want to optimize performance with incremental view maintenance.

    Average

    Use LiveAverage method if you want to optimize performance with incremental view maintenance.