asp.net - EF Core: how to load a single item from collection-nav property? -


i have one-to-many relationship between 2 entities: user (one) has messages (many) collection.
there needs display information user , @ same time needs load single message. try like:

mycontext.users.where(..).include(user => user.messages.take(1).first());

however code throws ecxeption

invalidoperationexception: property expression 'user=> {from message m in [chat].messages select [m] => take(1) => first()}' not valid. expression should represent property access: 't => t.myproperty'. more information on including related data, see http://go.microsoft.com/fwlink/?linkid=746393.

how can solve it?

you cannot way have tried.you have retrieve related messages db , after filter on memory (ienumerable) shown below.

var uselist= mycontext.users.where(..).include(user => user.messages);   foreach (var u in uselist)   {        var message= u.messages.take(1).first();    }

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