Hi,

I've found a LINQ translation error : this was working before (at least with 4.3 RC)

[attachment=0:1719v9hg]TestLinkBug.zip[/attachment:1719v9hg]

Model:

[Serializable]
  [HierarchyRoot]
  public class MyEntity : Entity
  {
    [Field, Key]
    public int Id { get; private set; }

    [Field]
    public string Text { get; set; }

    [Field, Association(PairTo = "LinkSource", OnOwnerRemove = OnRemoveAction.Cascade, OnTargetRemove = OnRemoveAction.Clear)]
    public EntitySet<Link> LinksFromThis { get; private set; }

    [Field, Association(PairTo = "LinkDestination", OnOwnerRemove = OnRemoveAction.Cascade, OnTargetRemove = OnRemoveAction.Clear)]
    public EntitySet<Link> LinksToThis { get; private set; }
  }

  [HierarchyRoot]
  public class Link : Entity
  {
    [Field, Key]
    public long Id { get; private set; }

    [Field]
    public MyEntity LinkSource { get; set; }

    [Field]
    public MyEntity LinkDestination { get; set; }
  }

Query

var query = from link in Query.All<Link>()
                      where link.LinkSource == source
                      where link.LinkDestination.Text == "test2"
                      select link.LinkDestination;

          query.ToList();

Exception:

Xtensive.Storage.Linq.TranslationException was unhandled
  Message=Unable to translate 'Query.All().Where(link => (link.LinkSource == @.source)).Where(link => (link.LinkDestination.Text == "test2")).Select(link => link.LinkDestination)' expression. See inner exception for details.
  Source=Xtensive.Storage
  StackTrace:
       at Xtensive.Storage.Linq.QueryProvider.Translate[TResult](Expression expression)
       at Xtensive.Storage.Linq.QueryProvider.Execute[TResult](Expression expression)
       at Xtensive.Storage.Linq.Queryable`1.GetEnumerator()
       at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)
       at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source)
       at TestLinkBug.Program.Main(String[] args) in c:\users\jbenoit.serensia\documents\visual studio 2010\Projects\TestLinkBug\TestLinkBug\Program.cs:line 45
       at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
       at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
       at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
       at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Threading.ThreadHelper.ThreadStart()
  InnerException: System.InvalidOperationException
       Message=Internal error: Unable to remap KeyExpression.
       Source=Xtensive.Storage
       StackTrace:
            at Xtensive.Storage.Linq.Expressions.KeyExpression.Remap(Int32[] map, Dictionary`2 processedExpressions)
            at Xtensive.Storage.Linq.Expressions.EntityExpression.Remap(Int32[] map, Dictionary`2 processedExpressions)
            at Xtensive.Storage.Linq.Expressions.EntityFieldExpression.Remap(Int32[] map, Dictionary`2 processedExpressions)
            at Xtensive.Storage.Linq.Expressions.ItemProjectorExpression.<>c__DisplayClass4.<Remap>b__3(IMappedExpression mapped)
            at Xtensive.Storage.Linq.Expressions.Visitors.GenericExpressionVisitor`1.VisitGenericExpression(T generic)
            at Xtensive.Storage.Linq.Expressions.Visitors.GenericExpressionVisitor`1.VisitUnknown(Expression e)
            at Xtensive.Core.Linq.ExpressionVisitor`1.Visit(Expression e)
            at Xtensive.Storage.Linq.Expressions.Visitors.GenericExpressionVisitor`1.Process(Expression target, Func`2 genericProcessor)
            at Xtensive.Storage.Linq.Expressions.ItemProjectorExpression.Remap(RecordSet dataSource, Int32[] columnMap)
            at Xtensive.Storage.Linq.Translator.Optimize(ProjectionExpression origin)
            at Xtensive.Storage.Linq.Translator.Translate[TResult](ProjectionExpression projection, IEnumerable`1 tupleParameterBindings)
            at Xtensive.Storage.Linq.Translator.Translate[TResult]()
            at Xtensive.Storage.Linq.QueryProvider.Translate[TResult](Expression expression)
       InnerException:

Regards, Julien

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