How do you use FirstOrDefault with Include?

Question

This works fine:

return Members
          .FirstOrDefault(m => m.Agreement.Equals(agreement));

But this throws an exception if it doesn't find a match:

 return Members
            .Include("Files")
            .FirstOrDefault(m => m.Agreement.Equals(agreement) &&
            !m.Files.Any(f => f.Status.Equals(12)));

So how can I get first/default (which may be null) when I'm using an Include?

The exception is:

Unexpected Exception at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.ConstantTranslator.TypedTranslate(ExpressionConverter parent, ConstantExpression linq) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TypedTranslator1.Translate(ExpressionConverter parent, Expression linq) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TranslateExpression(Expression linq) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.EqualsTranslator.TypedTranslate(ExpressionConverter parent, BinaryExpression linq) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TypedTranslator1.Translate(ExpressionConverter parent, Expression linq) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TranslateExpression(Expression linq) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TranslateLambda(LambdaExpression lambda, DbExpression input) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TranslateLambda(LambdaExpression lambda, DbExpression input, DbExpressionBinding& binding) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.MethodCallTranslator.OneLambdaTranslator.Translate(ExpressionConverter parent, MethodCallExpression call, DbExpression& source, DbExpressionBinding& sourceBinding, DbExpression& lambda) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.MethodCallTranslator.OneLambdaTranslator.Translate(ExpressionConverter parent, MethodCallExpression call) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.MethodCallTranslator.SequenceMethodTranslator.Translate(ExpressionConverter parent, MethodCallExpression call, SequenceMethod sequenceMethod)
at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.MethodCallTranslator.TypedTranslate(ExpressionConverter parent, MethodCallExpression linq) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TypedTranslator1.Translate(ExpressionConverter parent, Expression linq) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TranslateExpression(Expression linq) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.NotTranslator.TypedTranslate(ExpressionConverter parent, UnaryExpression linq) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TypedTranslator1.Translate(ExpressionConverter parent, Expression linq) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TranslateExpression(Expression linq) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.BinaryTranslator.TypedTranslate(ExpressionConverter parent, BinaryExpression linq) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TypedTranslator1.Translate(ExpressionConverter parent, Expression linq) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TranslateExpression(Expression linq) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TranslateLambda(LambdaExpression lambda, DbExpression input) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TranslateLambda(LambdaExpression lambda, DbExpression input, DbExpressionBinding& binding) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.MethodCallTranslator.OneLambdaTranslator.Translate(ExpressionConverter parent, MethodCallExpression call, DbExpression& source, DbExpressionBinding& sourceBinding, DbExpression& lambda) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.MethodCallTranslator.OneLambdaTranslator.Translate(ExpressionConverter parent, MethodCallExpression call) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.MethodCallTranslator.SequenceMethodTranslator.Translate(ExpressionConverter parent, MethodCallExpression call, SequenceMethod sequenceMethod)
at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.MethodCallTranslator.TypedTranslate(ExpressionConverter parent, MethodCallExpression linq) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TypedTranslator1.Translate(ExpressionConverter parent, Expression linq) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TranslateExpression(Expression linq) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.MethodCallTranslator.AggregateTranslator.Translate(ExpressionConverter parent, MethodCallExpression call) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.MethodCallTranslator.SequenceMethodTranslator.Translate(ExpressionConverter parent, MethodCallExpression call, SequenceMethod sequenceMethod)
at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.MethodCallTranslator.TypedTranslate(ExpressionConverter parent, MethodCallExpression linq) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TypedTranslator1.Translate(ExpressionConverter parent, Expression linq) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TranslateExpression(Expression linq) at System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.Convert()
at System.Data.Entity.Core.Objects.ELinq.ELinqQueryState.GetExecutionPlan(Nullable1 forMergeOption) at System.Data.Entity.Core.Objects.ObjectQuery1.<>c__DisplayClass7.<GetResults>b__6() at System.Data.Entity.Core.Objects.ObjectContext.ExecuteInTransaction[T](Func1 func, IDbExecutionStrategy executionStrategy, Boolean startLocalTransaction, Boolean releaseConnectionOnSuccess) at System.Data.Entity.Core.Objects.ObjectQuery1.<>c__DisplayClass7.<GetResults>b__5() at System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.Execute[TResult](Func1 operation) at System.Data.Entity.Core.Objects.ObjectQuery1.GetResults(Nullable1 forMergeOption) at System.Data.Entity.Core.Objects.ObjectQuery1.<System.Collections.Generic.IEnumerable<T>.GetEnumerator>b__0() at System.Data.Entity.Internal.LazyEnumerator1.MoveNext() at System.Linq.Enumerable.Single[TSource](IEnumerable1 source) at System.Data.Entity.Core.Objects.ELinq.ObjectQueryProvider.<GetElementFunction>b__3[TResult](IEnumerable1 sequence) at System.Data.Entity.Core.Objects.ELinq.ObjectQueryProvider.ExecuteSingle[TResult](IEnumerable1 query, Expression queryRoot) at System.Data.Entity.Core.Objects.ELinq.ObjectQueryProvider.System.Linq.IQueryProvider.Execute[TResult](Expression expression) at System.Data.Entity.Internal.Linq.DbQueryProvider.Execute[TResult](Expression expression) at System.Linq.Queryable.Count[TSource](IQueryable1 source)

Answer 1

How about this:

return Members
    .Include("Files")
    .Where(m => m.Agreement.Equals(agreement) &&
                m.Files != null &&
               !m.Files.Any(f => f.Status.Equals(12)))
    .FirstOrDefault();

Answer 2

Using Microsoft.EntityFrameworkCore 3.1.7 this works fine:

var myEntity = await dbContext.MyEntities.Include(x => x.MyOtherEntities).FirstOrDefaultAsync(x => x.Name == "Not existing name");