Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Data.Entity/System/Data/Query/InternalTrees/AncillaryOps.cs

@@ -0,0 +1,100 @@
+//---------------------------------------------------------------------
+// <copyright file="AnciliaryOps.cs" company="Microsoft">
+//      Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//
+// @owner  [....]
+// @backupOwner [....]
+//---------------------------------------------------------------------
+
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Globalization;
+
+namespace System.Data.Query.InternalTrees
+{
+    /// <summary>
+    /// A definition of a variable
+    /// </summary>
+    internal sealed class VarDefOp : AncillaryOp
+    {
+        #region private state
+        private Var m_var;
+        #endregion
+
+        #region constructors
+        internal VarDefOp(Var v) : this()
+        { 
+            m_var = v; 
+        }
+        private VarDefOp() : base(OpType.VarDef) { }
+        #endregion
+
+        #region public methods
+        internal static readonly VarDefOp Pattern = new VarDefOp();
+
+        /// <summary>
+        /// 1 child - the defining expression
+        /// </summary>
+        internal override int Arity { get { return 1; } }
+
+        /// <summary>
+        /// The Var being defined
+        /// </summary>
+        internal Var Var { get { return m_var; } }
+
+        /// <summary>
+        /// Visitor pattern method
+        /// </summary>
+        /// <param name="v">The BasicOpVisitor that is visiting this Op</param>
+        /// <param name="n">The Node that references this Op</param>
+        [DebuggerNonUserCode]
+        internal override void Accept(BasicOpVisitor v, Node n) { v.Visit(this, n); }
+        
+        /// <summary>
+        /// Visitor pattern method for visitors with a return value
+        /// </summary>
+        /// <param name="v">The visitor</param>
+        /// <param name="n">The node in question</param>
+        /// <returns>An instance of TResultType</returns>
+        [DebuggerNonUserCode]
+        internal override TResultType Accept<TResultType>(BasicOpVisitorOfT<TResultType> v, Node n) { return v.Visit(this, n); }
+        #endregion
+    }
+
+    /// <summary>
+    /// Helps define a list of VarDefOp
+    /// </summary>
+    internal sealed class VarDefListOp : AncillaryOp
+    {
+        #region constructors
+        private VarDefListOp() : base(OpType.VarDefList) { }
+        #endregion
+
+        #region public methods
+        /// <summary>
+        /// singleton instance
+        /// </summary>
+        internal static readonly VarDefListOp Instance = new VarDefListOp();
+        internal static readonly VarDefListOp Pattern = Instance;
+
+        /// <summary>
+        /// Visitor pattern method
+        /// </summary>
+        /// <param name="v">The BasicOpVisitor that is visiting this Op</param>
+        /// <param name="n">The Node that references this Op</param>
+        [DebuggerNonUserCode]
+        internal override void Accept(BasicOpVisitor v, Node n) { v.Visit(this, n); }
+        
+        /// <summary>
+        /// Visitor pattern method for visitors with a return value
+        /// </summary>
+        /// <param name="v">The visitor</param>
+        /// <param name="n">The node in question</param>
+        /// <returns>An instance of TResultType</returns>
+        [DebuggerNonUserCode]
+        internal override TResultType Accept<TResultType>(BasicOpVisitorOfT<TResultType> v, Node n) { return v.Visit(this, n); }
+        #endregion
+    }
+}

mcs/class/referencesource/System.Data.Entity/System/Data/Query/InternalTrees/BasicValidator.cs

@@ -0,0 +1,478 @@
+//---------------------------------------------------------------------
+// <copyright file="BasicValidator.cs" company="Microsoft">
+//      Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//
+// @owner  simoncav
+// @backupOwner katicad
+//---------------------------------------------------------------------
+
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.Diagnostics;
+using System.Data;
+using System.Data.Common;
+using System.Data.Metadata.Edm;
+
+namespace System.Data.Query.InternalTrees
+{
+#if DEBUG
+    /// <summary>
+    /// The BasicValidator validates the shape of the IQT. It ensures that the 
+    /// various Ops in the tree have the right kinds and number of arguments.
+    /// </summary>
+    internal class BasicValidator : BasicOpVisitor
+    {
+        #region constructors
+        protected BasicValidator(Command command)
+        {
+            m_command = command;
+        }
+        #endregion
+
+        #region private surface
+        protected void Validate(Node node)
+        {
+            VisitNode(node);
+        }
+
+        #region AssertHelpers
+        protected static void Assert(bool condition, string format, int arg0)
+        {
+            if (!condition)
+            {
+                Debug.Assert(false, String.Format(CultureInfo.InvariantCulture, format, arg0));
+            }
+        }
+        protected static void Assert(bool condition, string format, OpType op)
+        {
+            if (!condition)
+            {
+                Debug.Assert(false, String.Format(CultureInfo.InvariantCulture, format, Dump.AutoString.ToString(op)));
+            }
+        }
+        protected static void Assert(bool condition, string format, OpType op, object arg1)
+        {
+            if (!condition)
+            {
+                Debug.Assert(false, String.Format(CultureInfo.InvariantCulture, format, Dump.AutoString.ToString(op), arg1));
+            }
+        }
+        protected static void Assert(bool condition, string format, OpType op, object arg1, object arg2)
+        {
+            if (!condition)
+            {
+                Debug.Assert(false, String.Format(CultureInfo.InvariantCulture, format, Dump.AutoString.ToString(op), arg1, arg2));
+            }
+        }
+        protected static void Assert(bool condition, string format, params object[] args)
+        {
+            if (!condition)
+            {
+                Debug.Assert(false, String.Format(CultureInfo.InvariantCulture, format, args));
+            }
+        }
+        protected static void AssertArity(Node n, int arity)
+        {
+            Assert(arity == n.Children.Count, "Op Arity mismatch for Op {0}: Expected {1} arguments; found {2} arguments", n.Op.OpType, arity, n.Children.Count);
+        }
+        protected static void AssertArity(Node n)
+        {
+            if (n.Op.Arity != Op.ArityVarying)
+            {
+                AssertArity(n, n.Op.Arity);
+            }
+        }
+        protected static void AssertBoolean(TypeUsage type)
+        {
+            Assert(TypeSemantics.IsPrimitiveType(type, PrimitiveTypeKind.Boolean), "Type Mismatch: Expected Boolean; found {0} instead", TypeHelpers.GetFullName(type));
+        }
+        protected static void AssertCollectionType(TypeUsage type)
+        {
+            Assert(TypeSemantics.IsCollectionType(type), "Type Mismatch: Expected Collection type: Found {0}", TypeHelpers.GetFullName(type));
+        }
+        protected static void AssertEqualTypes(TypeUsage type1, TypeUsage type2)
+        {
+            Assert(Command.EqualTypes(type1, type2),
+                "Type mismatch: " + type1.Identity + ", " + type2.Identity);
+        }
+        protected static void AssertEqualTypes(TypeUsage type1, EdmType type2)
+        {
+            AssertEqualTypes(type1, TypeUsage.Create(type2));
+        }
+        protected static void AssertBooleanOp(Op op)
+        {
+            AssertBoolean(op.Type);
+        }
+        protected static void AssertRelOp(Op op)
+        {
+            Assert(op.IsRelOp, "OpType Mismatch: Expected RelOp; found {0}", op.OpType);
+        }
+        protected static void AssertRelOpOrPhysicalOp(Op op)
+        {
+            Assert(op.IsRelOp || op.IsPhysicalOp, "OpType Mismatch: Expected RelOp or PhysicalOp; found {0}", op.OpType);
+        }
+        protected static void AssertScalarOp(Op op)
+        {
+            Assert(op.IsScalarOp, "OpType Mismatch: Expected ScalarOp; found {0}", op.OpType);
+        }
+        protected static void AssertOpType(Op op, OpType opType)
+        {
+            Assert(op.OpType == opType, "OpType Mismatch: Expected {0}; found {1}", op.OpType, Dump.AutoString.ToString(opType));
+        }
+        protected static void AssertUnexpectedOp(Op op)
+        {
+            Assert(false, "Unexpected OpType {0}", op.OpType);
+        }
+        #endregion
+
+        #region Visitors
+
+        protected override void VisitDefault(Node n)
+        {
+            Assert(n.Id >= 0, "Bad node id {0}", n.Id);
+            VisitChildren(n);
+            AssertArity(n);
+        }
+
+        #region ScalarOps
+        protected override void VisitScalarOpDefault(ScalarOp op, Node n)
+        {
+            VisitDefault(n);
+            Assert(op.Type != null, "ScalarOp {0} with no datatype!", op.OpType);
+            if (op.OpType != OpType.Element &&
+                op.OpType != OpType.Exists &&
+                op.OpType != OpType.Collect)
+            {
+                foreach (Node chi in n.Children)
+                {
+                    AssertScalarOp(chi.Op);
+                }
+            }
+        }
+
+        public override void Visit(AggregateOp op, Node n)
+        {
+            VisitScalarOpDefault(op, n);
+        }
+        public override void Visit(CaseOp op, Node n)
+        {
+            VisitScalarOpDefault(op, n);
+            Assert((n.Children.Count >= 3 && n.Children.Count % 2 == 1),
+                   "CaseOp: Expected odd number of arguments, and at least 3; found {0}", n.Children.Count); 
+           
+            // Validate that each when statement is of type Boolean
+            for (int i = 0; i < n.Children.Count - 1; i += 2)
+            {
+                Assert(TypeSemantics.IsBooleanType(n.Children[i].Op.Type), "Encountered a when node with a non-boolean return type");
+            }
+
+            // Ensure that the then clauses, the else clause and the result type are all the same
+            for (int i = 1; i < n.Children.Count-1; i += 2)
+            {
+                AssertEqualTypes(n.Op.Type, n.Children[i].Op.Type);
+            }
+            AssertEqualTypes(n.Op.Type, n.Children[n.Children.Count - 1].Op.Type);
+        }
+
+        public override void Visit(ComparisonOp op, Node n)
+        {
+            VisitScalarOpDefault(op, n);
+            AssertBooleanOp(op);
+            AssertEqualTypes(n.Child0.Op.Type, n.Child1.Op.Type);
+        }
+        public override void Visit(ConditionalOp op, Node n)
+        {
+            VisitScalarOpDefault(op, n);
+            switch(op.OpType)
+            {
+                case OpType.And: 
+                case OpType.Or:
+                    AssertArity(n, 2);
+                    AssertBooleanOp(n.Child0.Op);
+                    AssertBooleanOp(n.Child1.Op);
+                    break;
+                case OpType.Not:
+                    AssertArity(n, 1);
+                    AssertBooleanOp(n.Child0.Op);
+                    break;
+                case OpType.IsNull:
+                    AssertArity(n, 1);
+                    break;
+                default:
+                    AssertUnexpectedOp(op);
+                    break;
+            }
+            AssertBooleanOp(op);
+        }
+        public override void Visit(ArithmeticOp op, Node n)
+        {
+            VisitScalarOpDefault(op, n);
+            switch (op.OpType)
+            {
+                case OpType.Plus: 
+                case OpType.Minus: 
+                case OpType.Multiply: 
+                case OpType.Divide:
+                case OpType.Modulo:
+                    AssertEqualTypes(n.Child0.Op.Type, n.Child1.Op.Type);
+                    AssertEqualTypes(n.Op.Type, n.Child0.Op.Type);
+                    AssertArity(n, 2);
+                    break;
+                case OpType.UnaryMinus: 
+                    AssertArity(n, 1);
+                    break;
+                default:
+                    AssertUnexpectedOp(op);
+                    break;
+            }
+        }
+        public override void Visit(ElementOp op, Node n)
+        {
+            VisitScalarOpDefault(op, n);
+            AssertRelOp(n.Child0.Op);
+        }
+
+        public override void Visit(CollectOp op, Node n)
+        {
+            VisitScalarOpDefault(op, n);
+            AssertOpType(n.Child0.Op, OpType.PhysicalProject);
+            AssertCollectionType(op.Type);
+        }
+
+        public override void Visit(DerefOp op, Node n)
+        {
+            VisitScalarOpDefault(op, n);
+            Assert(TypeSemantics.IsEntityType(op.Type), "Expected an entity type. Found " + op.Type);
+            Assert(TypeSemantics.IsReferenceType(n.Child0.Op.Type), "Expected a ref type. Found " + n.Child0.Op.Type);
+            RefType r = n.Child0.Op.Type.EdmType as RefType;
+            Assert(r.ElementType.EdmEquals(op.Type.EdmType), "Inconsistent types");
+        }
+
+        public override void Visit(ExistsOp op, Node n)
+        {
+            VisitScalarOpDefault(op, n);
+            AssertRelOp(n.Child0.Op);
+            AssertBooleanOp(op);
+        }
+
+        public override void Visit(PropertyOp op, Node n)
+        {
+            VisitScalarOpDefault(op, n);
+            AssertEqualTypes(n.Child0.Op.Type, op.PropertyInfo.DeclaringType);
+        }
+
+        public override void Visit(RelPropertyOp op, Node n)
+        {
+            VisitScalarOpDefault(op, n);
+            Assert(m_command.IsRelPropertyReferenced(op.PropertyInfo), "no such rel property:", op.PropertyInfo);
+            Assert(TypeSemantics.IsEntityType(n.Child0.Op.Type), "argument to RelPropertyOp must be an entity type. Found: ", n.Child0.Op.Type);
+        }
+
+        public override void Visit(FunctionOp op, Node n)
+        {
+            VisitScalarOpDefault(op, n);
+            Assert(op.Function.Parameters.Count == n.Children.Count, "FunctionOp: Argument count ({0}) does not match parameter count ({1})", n.Children.Count, op.Function.Parameters.Count);
+            for (int idx = 0; idx < n.Children.Count; idx++)
+            {
+                AssertEqualTypes(n.Children[idx].Op.Type, op.Function.Parameters[idx].TypeUsage);
+            }
+        }
+
+        public override void Visit(SoftCastOp op, Node n)
+        {
+            VisitScalarOpDefault(op, n);
+            // Aconrad 9/21/06 - temporarily removing check here 
+            //  because the assert wrongly fails in some cases where the types are promotable,
+            //  but the facets are not.  Put this back when that issue is solved.
+            // Assert(TypeSemantics.IsEquivalentOrPromotableTo(n.Child0.Op.Type, op.Type), "Illegal SoftCastOp: Cannot promote input type {0} to target type {1}", n.Child0.Op.Type.Identity, op.Type.Identity);
+        }
+
+        public override void Visit(NavigateOp op, Node n)
+        {
+            VisitScalarOpDefault(op, n);
+        }
+
+        #endregion
+
+        #region AncillaryOps
+        protected override void VisitAncillaryOpDefault(AncillaryOp op, Node n)
+        {
+            VisitDefault(n);
+        }
+
+        public override void Visit(VarDefOp op, Node n)
+        {
+            VisitAncillaryOpDefault(op, n);
+            AssertScalarOp(n.Child0.Op);
+            VarDefOp varDefOp = (VarDefOp)op;
+            AssertEqualTypes(varDefOp.Var.Type, n.Child0.Op.Type);
+        }
+        public override void Visit(VarDefListOp op, Node n)
+        {
+            VisitDefault(n);
+            foreach (Node chi in n.Children)
+            {
+                AssertOpType(chi.Op, OpType.VarDef);
+            }
+        }
+        #endregion
+
+        #region RelOps
+        protected override void VisitRelOpDefault(RelOp op, Node n)
+        {
+            VisitDefault(n);
+        }
+        protected override void VisitJoinOp(JoinBaseOp op, Node n)
+        {
+            VisitRelOpDefault(op, n);
+            if (op.OpType == OpType.CrossJoin)
+            {
+                Assert(n.Children.Count >= 2, "CrossJoinOp needs at least 2 arguments; found only {0}", n.Children.Count);
+                return;
+            }
+            AssertRelOpOrPhysicalOp(n.Child0.Op);
+            AssertRelOpOrPhysicalOp(n.Child1.Op);
+            AssertScalarOp(n.Child2.Op);
+            AssertBooleanOp(n.Child2.Op);
+        }
+        protected override void VisitApplyOp(ApplyBaseOp op, Node n)
+        {
+             VisitRelOpDefault(op, n);
+             AssertRelOpOrPhysicalOp(n.Child0.Op);
+             AssertRelOpOrPhysicalOp(n.Child1.Op);
+        }
+        protected override void VisitSetOp(SetOp op, Node n)
+        {
+             VisitRelOpDefault(op, n);
+             AssertRelOpOrPhysicalOp(n.Child0.Op);
+             AssertRelOpOrPhysicalOp(n.Child1.Op);
+             //
+             // Ensure that the corresponding setOp Vars are all of the same
+             // type
+             //
+             foreach (VarMap varMap in op.VarMap)
+             {
+                 foreach (KeyValuePair<Var, Var> kv in varMap)
+                 {
+                     AssertEqualTypes(kv.Key.Type, kv.Value.Type);
+                 }
+             }
+        }
+        protected override void VisitSortOp(SortBaseOp op, Node n)
+        {
+            VisitRelOpDefault(op, n);
+            AssertRelOpOrPhysicalOp(n.Child0.Op);
+        }
+
+        public override void Visit(ConstrainedSortOp op, Node n)
+        {
+            base.Visit(op, n);
+            AssertScalarOp(n.Child1.Op);
+            Assert(TypeSemantics.IsIntegerNumericType(n.Child1.Op.Type), "ConstrainedSortOp Skip Count Node must have an integer result type");
+            AssertScalarOp(n.Child2.Op);
+            Assert(TypeSemantics.IsIntegerNumericType(n.Child2.Op.Type), "ConstrainedSortOp Limit Node must have an integer result type");
+        }
+
+        public override void Visit(ScanTableOp op, Node n)
+        {
+            VisitRelOpDefault(op, n);
+        }
+        public override void Visit(ScanViewOp op, Node n)
+        {
+            VisitRelOpDefault(op, n);
+            AssertRelOp(n.Child0.Op);
+        }
+        public override void Visit(FilterOp op, Node n)
+        {
+            VisitRelOpDefault(op, n);
+            AssertRelOpOrPhysicalOp(n.Child0.Op);
+            AssertScalarOp(n.Child1.Op);
+            AssertBooleanOp(n.Child1.Op);
+        }
+        public override void Visit(ProjectOp op, Node n)
+        {
+            VisitRelOpDefault(op, n);
+            AssertRelOpOrPhysicalOp(n.Child0.Op);
+            AssertOpType(n.Child1.Op, OpType.VarDefList);
+        }
+        public override void Visit(UnnestOp op, Node n)
+        {
+            VisitRelOpDefault(op, n);
+            AssertOpType(n.Child0.Op, OpType.VarDef);
+        }
+        protected override void VisitGroupByOp(GroupByBaseOp op, Node n)
+        {
+            VisitRelOpDefault(op, n);
+            AssertRelOpOrPhysicalOp(n.Child0.Op);
+
+            for (int i = 1; i < n.Children.Count; i++)
+            {
+                AssertOpType(n.Children[i].Op, OpType.VarDefList);
+            }
+        }
+        public override void Visit(GroupByIntoOp op, Node n)
+        {
+            VisitGroupByOp(op, n);
+            Assert(n.Child3.Children.Count > 0, "GroupByInto with no group aggregate vars");
+        }
+        
+        public override void Visit(DistinctOp op, Node n)
+        {
+            VisitRelOpDefault(op, n);
+            AssertRelOp(n.Child0.Op);
+        }
+
+        public override void Visit(SingleRowTableOp op, Node n)
+        {
+            VisitRelOpDefault(op, n);
+        }
+        public override void Visit(SingleRowOp op, Node n)
+        {
+            VisitRelOpDefault(op, n);
+            AssertRelOpOrPhysicalOp(n.Child0.Op);
+        }
+        #endregion
+
+        #region PhysicalOps
+        protected override void VisitPhysicalOpDefault(PhysicalOp op, Node n)
+        {
+            VisitDefault(n);
+        }
+        public override void Visit(PhysicalProjectOp op, Node n)
+        {
+            VisitPhysicalOpDefault(op, n);
+            Assert(n.Children.Count >= 1, "PhysicalProjectOp needs at least 1 arg: found {0}", n.Children.Count);
+            foreach (Node chi in n.Children)
+            {
+                AssertRelOpOrPhysicalOp(chi.Op);
+            }
+        }
+        public override void Visit(SingleStreamNestOp op, Node n)
+        {
+            VisitPhysicalOpDefault(op, n);
+            AssertRelOp(n.Child0.Op);
+        }
+        public override void Visit(MultiStreamNestOp op, Node n)
+        {
+            VisitPhysicalOpDefault(op, n);
+            Assert(n.Children.Count > 1, "MultiStreamNestOp needs at least 2 arguments: found {0}", n.Children.Count);
+            foreach (Node chi in n.Children)
+            {
+                AssertRelOpOrPhysicalOp(chi.Op);
+            }
+        }
+        #endregion
+
+        #endregion
+
+        #endregion
+
+        #region private state
+        private Command m_command;
+        #endregion
+
+    }
+#endif // DEBUG
+}

mcs/class/referencesource/System.Data.Entity/System/Data/Query/InternalTrees/ColumnMapCopier.cs

@@ -0,0 +1,304 @@
+//---------------------------------------------------------------------
+// <copyright file="ColumnMapCopier.cs" company="Microsoft">
+//      Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//
+// @owner  [....]
+// @backupOwner [....]
+//---------------------------------------------------------------------
+
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.Diagnostics;
+using System.Data.Query.InternalTrees;
+using System.Data.Query.PlanCompiler;
+using System.Linq;
+using System.Data.Mapping;
+using System.Data.Metadata.Edm;
+
+namespace System.Data.Query.InternalTrees
+{
+    /// <summary>
+    /// The ColumnMapCopier clones an entire ColumnMap hierarchy; this is different
+    /// than the ColumnMapTranslator, which only copies things that need to be copied.
+    /// 
+    /// Note that this is a stateless visitor; it uses the visitor's argument for its
+    /// state management.
+    /// 
+    /// The Visitor's argument is a VarMap; anytime a Var is found in the ColumnMap 
+    /// hierarchy, it is replaced with the replacement from the VarMap.
+    /// 
+    /// Note also that previous implementations of this class attempted to avoid re-
+    /// processing ColumnMaps by caching the results for each input and returning it.
+    /// I wasn't convinced that we were buying much with all that caching, since the 
+    /// only ColumnMaps that should be repeated in the hierarchy are simple ones; there 
+    /// is about as much object creation either way.  The only reason I see that we 
+    /// want to cache these is if we really cared to have only one VarRefColumnMap 
+    /// instance for a given Var and be able to use reference equality instead of
+    /// comparing the Vars themselves.  I don't believe we're making that guarantee
+    /// anywhere else, so I've removed that for now because I don't want the added 
+    /// complexity that the caching adds.  If performance analysis indicates there is 
+    /// a problem, we can considier addding the cache back in.
+    /// </summary>
+    internal class ColumnMapCopier : ColumnMapVisitorWithResults<ColumnMap, VarMap>
+    {
+
+        #region Constructors
+
+        /// <summary>
+        /// Singleton instance for the "public" methods to use;
+        /// </summary>
+        static private ColumnMapCopier Instance = new ColumnMapCopier();
+
+        /// <summary>
+        /// Constructor; no one should use this.
+        /// </summary>
+        private ColumnMapCopier()
+        {
+        }
+
+        #endregion
+
+        #region "Public" surface area
+
+        /// <summary>
+        /// Return a copy of the column map, replacing all vars with the replacements
+        /// found in the replacementVarMap
+        /// </summary>
+        /// <param name="columnMap"></param>
+        /// <param name="replacementVarMap"></param>
+        /// <returns></returns>
+        internal static ColumnMap Copy(ColumnMap columnMap, VarMap replacementVarMap)
+        {
+            return columnMap.Accept(Instance, replacementVarMap);
+        }
+
+        #endregion
+
+        #region Visitor Helpers
+
+        /// <summary>
+        /// Returns the var to use in the copy, either the original or the
+        /// replacement.  Note that we will follow the chain of replacements, in
+        /// case the replacement was also replaced.
+        /// </summary>
+        /// <param name="originalVar"></param>
+        /// <param name="replacementVarMap"></param>
+        /// <returns></returns>
+        private static Var GetReplacementVar(Var originalVar, VarMap replacementVarMap)
+        {
+            // SQLBUDT #478509: Follow the chain of mapped vars, don't
+            //                  just stop at the first one
+            Var replacementVar = originalVar;
+
+            while (replacementVarMap.TryGetValue(replacementVar, out originalVar))
+            {
+                if (originalVar == replacementVar)
+                {
+                    break;
+                }
+                replacementVar = originalVar;
+            }
+            return replacementVar;
+        }
+
+        #endregion
+
+        #region Visitor Methods
+
+        #region List handling
+
+        /// <summary>
+        /// Copies the List of ColumnMaps or SimpleColumnMaps
+        /// </summary>
+        /// <typeparam name="TListType"></typeparam>
+        /// <param name="tList"></param>
+        /// <param name="replacementVarMap"></param>
+        /// <returns></returns>
+        internal TListType[] VisitList<TListType>(TListType[] tList, VarMap replacementVarMap)
+            where TListType : ColumnMap
+        {
+            TListType[] newTList = new TListType[tList.Length];
+            for(int i = 0; i < tList.Length; ++i) {
+                newTList[i] = (TListType)tList[i].Accept(this, replacementVarMap);
+            }
+            return newTList;
+        }
+
+        #endregion
+
+        #region EntityIdentity handling
+
+        /// <summary>
+        /// Copies the DiscriminatedEntityIdentity
+        /// </summary>
+        /// <param name="entityIdentity"></param>
+        /// <param name="replacementVarMap"></param>
+        /// <returns></returns>
+        protected override EntityIdentity VisitEntityIdentity(DiscriminatedEntityIdentity entityIdentity, VarMap replacementVarMap)
+        {
+            SimpleColumnMap newEntitySetCol = (SimpleColumnMap)entityIdentity.EntitySetColumnMap.Accept(this, replacementVarMap);
+            SimpleColumnMap[] newKeys = VisitList(entityIdentity.Keys, replacementVarMap);
+            return new DiscriminatedEntityIdentity(newEntitySetCol, entityIdentity.EntitySetMap, newKeys);
+        }
+
+        /// <summary>
+        /// Copies the SimpleEntityIdentity
+        /// </summary>
+        /// <param name="entityIdentity"></param>
+        /// <param name="replacementVarMap"></param>
+        /// <returns></returns>
+        protected override EntityIdentity VisitEntityIdentity(SimpleEntityIdentity entityIdentity, VarMap replacementVarMap)
+        {
+            SimpleColumnMap[] newKeys = VisitList(entityIdentity.Keys, replacementVarMap);
+            return new SimpleEntityIdentity(entityIdentity.EntitySet, newKeys);
+        }
+
+        #endregion
+
+        /// <summary>
+        /// ComplexTypeColumnMap
+        /// </summary>
+        /// <param name="columnMap"></param>
+        /// <param name="replacementVarMap"></param>
+        /// <returns></returns>
+        internal override ColumnMap Visit(ComplexTypeColumnMap columnMap, VarMap replacementVarMap)
+        {
+            SimpleColumnMap newNullability = columnMap.NullSentinel;
+            if (null != newNullability)
+            {
+                newNullability = (SimpleColumnMap)newNullability.Accept(this, replacementVarMap);
+            }
+            ColumnMap[] fieldList = VisitList(columnMap.Properties, replacementVarMap);
+            return new ComplexTypeColumnMap(columnMap.Type, columnMap.Name, fieldList, newNullability);
+        }
+
+        /// <summary>
+        /// DiscriminatedCollectionColumnMap
+        /// </summary>
+        /// <param name="columnMap"></param>
+        /// <param name="replacementVarMap"></param>
+        /// <returns></returns>
+        internal override ColumnMap Visit(DiscriminatedCollectionColumnMap columnMap, VarMap replacementVarMap)
+        {
+            ColumnMap newElementColumnMap = columnMap.Element.Accept(this, replacementVarMap);
+            SimpleColumnMap newDiscriminator = (SimpleColumnMap)columnMap.Discriminator.Accept(this, replacementVarMap);
+            SimpleColumnMap[] newKeys = VisitList(columnMap.Keys, replacementVarMap);
+            SimpleColumnMap[] newForeignKeys = VisitList(columnMap.ForeignKeys, replacementVarMap);
+            return new DiscriminatedCollectionColumnMap(columnMap.Type, columnMap.Name, newElementColumnMap, newKeys, newForeignKeys, newDiscriminator, columnMap.DiscriminatorValue);
+        }
+
+        /// <summary>
+        /// EntityColumnMap
+        /// </summary>
+        /// <param name="columnMap"></param>
+        /// <param name="replacementVarMap"></param>
+        /// <returns></returns>
+        internal override ColumnMap Visit(EntityColumnMap columnMap, VarMap replacementVarMap)
+        {
+            EntityIdentity newEntityIdentity = VisitEntityIdentity(columnMap.EntityIdentity, replacementVarMap);
+            ColumnMap[] fieldList = VisitList(columnMap.Properties, replacementVarMap);
+            return new EntityColumnMap(columnMap.Type, columnMap.Name, fieldList, newEntityIdentity);
+        }
+
+        /// <summary>
+        /// SimplePolymorphicColumnMap
+        /// </summary>
+        /// <param name="columnMap"></param>
+        /// <param name="replacementVarMap"></param>
+        /// <returns></returns>
+        internal override ColumnMap Visit(SimplePolymorphicColumnMap columnMap, VarMap replacementVarMap)
+        {
+            SimpleColumnMap newDiscriminator = (SimpleColumnMap)columnMap.TypeDiscriminator.Accept(this, replacementVarMap);
+
+            Dictionary<object, TypedColumnMap> newTypeChoices = new Dictionary<object, TypedColumnMap>(columnMap.TypeChoices.Comparer);
+            foreach (KeyValuePair<object, TypedColumnMap> kv in columnMap.TypeChoices)
+            {
+                TypedColumnMap newMap = (TypedColumnMap)kv.Value.Accept(this, replacementVarMap);
+                newTypeChoices[kv.Key] = newMap;
+            }
+            ColumnMap[] newBaseFieldList = VisitList(columnMap.Properties, replacementVarMap);
+            return new SimplePolymorphicColumnMap(columnMap.Type, columnMap.Name, newBaseFieldList, newDiscriminator, newTypeChoices);
+        }
+
+        /// <summary>
+        /// MultipleDiscriminatorPolymorphicColumnMap
+        /// </summary>
+        internal override ColumnMap Visit(MultipleDiscriminatorPolymorphicColumnMap columnMap, VarMap replacementVarMap)
+        {
+            // At this time, we shouldn't ever see this type here; it's for SPROCS which don't use
+            // the plan compiler.
+            System.Data.Query.PlanCompiler.PlanCompiler.Assert(false, "unexpected MultipleDiscriminatorPolymorphicColumnMap in ColumnMapCopier");
+            return null;
+        }
+
+        /// <summary>
+        /// RecordColumnMap
+        /// </summary>
+        /// <param name="columnMap"></param>
+        /// <param name="replacementVarMap"></param>
+        /// <returns></returns>
+        internal override ColumnMap Visit(RecordColumnMap columnMap, VarMap replacementVarMap)
+        {
+            SimpleColumnMap newNullability = columnMap.NullSentinel;
+            if (null != newNullability)
+            {
+                newNullability = (SimpleColumnMap)newNullability.Accept(this, replacementVarMap);
+            }
+            ColumnMap[] fieldList = VisitList(columnMap.Properties, replacementVarMap);
+            return new RecordColumnMap(columnMap.Type, columnMap.Name, fieldList, newNullability);
+        }
+
+        /// <summary>
+        /// RefColumnMap
+        /// </summary>
+        /// <param name="columnMap"></param>
+        /// <param name="replacementVarMap"></param>
+        /// <returns></returns>
+        internal override ColumnMap Visit(RefColumnMap columnMap, VarMap replacementVarMap)
+        {
+            EntityIdentity newEntityIdentity = VisitEntityIdentity(columnMap.EntityIdentity, replacementVarMap);
+            return new RefColumnMap(columnMap.Type, columnMap.Name, newEntityIdentity);
+        }
+
+        /// <summary>
+        /// ScalarColumnMap
+        /// </summary>
+        /// <param name="columnMap"></param>
+        /// <param name="replacementVarMap"></param>
+        /// <returns></returns>
+        internal override ColumnMap Visit(ScalarColumnMap columnMap, VarMap replacementVarMap)
+        {
+            return new ScalarColumnMap(columnMap.Type, columnMap.Name, columnMap.CommandId, columnMap.ColumnPos);
+        }
+
+        /// <summary>
+        /// SimpleCollectionColumnMap
+        /// </summary>
+        /// <param name="columnMap"></param>
+        /// <param name="replacementVarMap"></param>
+        /// <returns></returns>
+        internal override ColumnMap Visit(SimpleCollectionColumnMap columnMap, VarMap replacementVarMap)
+        {
+            ColumnMap newElementColumnMap = columnMap.Element.Accept(this, replacementVarMap);
+            SimpleColumnMap[] newKeys = VisitList(columnMap.Keys, replacementVarMap);
+            SimpleColumnMap[] newForeignKeys = VisitList(columnMap.ForeignKeys, replacementVarMap);
+            return new SimpleCollectionColumnMap(columnMap.Type, columnMap.Name, newElementColumnMap, newKeys, newForeignKeys);
+        }
+
+        /// <summary>
+        /// VarRefColumnMap
+        /// </summary>
+        /// <param name="columnMap"></param>
+        /// <param name="replacementVarMap"></param>
+        /// <returns></returns>
+        internal override ColumnMap Visit(VarRefColumnMap columnMap, VarMap replacementVarMap)
+        {
+            Var replacementVar = GetReplacementVar(columnMap.Var, replacementVarMap);
+            return new VarRefColumnMap(columnMap.Type, columnMap.Name, replacementVar);
+        }
+
+        #endregion
+    }
+}

mcs/class/referencesource/System.Data.Entity/System/Data/Query/InternalTrees/ColumnMapFactory.cs

@@ -0,0 +1,394 @@
+//------------------------------------------------------------------------------
+// <copyright file="ColumnMapFactory.cs" company="Microsoft">
+//      Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+// @owner  [....]
+// @backupOwner [....]
+//------------------------------------------------------------------------------
+
+using System.Collections.Generic;
+using System.Data.Common;
+using System.Data.Common.Utils;
+using System.Data.Entity;
+using System.Data.Mapping;
+using System.Data.Metadata.Edm;
+using System.Data.Objects.ELinq;
+using System.Diagnostics;
+using System.Linq;
+using System.Linq.Expressions;
+using System.Reflection;
+
+namespace System.Data.Query.InternalTrees
+{
+    /// <summary>
+    /// Factory methods for prescriptive column map patterns (includes default
+    /// column maps for -- soon to be -- public materializer services and function
+    /// mappings).
+    /// </summary>
+    internal static class ColumnMapFactory
+    {
+        /// <summary>
+        /// Creates a column map for the given reader and function mapping.
+        /// </summary>
+        internal static CollectionColumnMap CreateFunctionImportStructuralTypeColumnMap(DbDataReader storeDataReader, FunctionImportMappingNonComposable mapping, int resultSetIndex, EntitySet entitySet, StructuralType baseStructuralType)
+        {
+            FunctionImportStructuralTypeMappingKB resultMapping = mapping.GetResultMapping(resultSetIndex);
+            Debug.Assert(resultMapping != null);
+            if (resultMapping.NormalizedEntityTypeMappings.Count == 0) // no explicit mapping; use default non-polymorphic reader
+            {
+                // if there is no mapping, create default mapping to root entity type or complex type
+                Debug.Assert(!baseStructuralType.Abstract, "mapping loader must verify abstract types have explicit mapping");
+               
+                return CreateColumnMapFromReaderAndType(storeDataReader, baseStructuralType, entitySet, resultMapping.ReturnTypeColumnsRenameMapping);
+            }
+            
+            // the section below deals with the polymorphic entity type mapping for return type
+            EntityType baseEntityType = baseStructuralType as EntityType;
+            Debug.Assert(null != baseEntityType, "We should have entity type here");
+
+            // Generate column maps for all discriminators
+            ScalarColumnMap[] discriminatorColumns = CreateDiscriminatorColumnMaps(storeDataReader, mapping, resultSetIndex);
+
+            // Generate default maps for all mapped entity types
+            var mappedEntityTypes = new HashSet<EntityType>(resultMapping.MappedEntityTypes);
+            mappedEntityTypes.Add(baseEntityType); // make sure the base type is represented
+            Dictionary<EntityType, TypedColumnMap> typeChoices = new Dictionary<EntityType, TypedColumnMap>(mappedEntityTypes.Count);
+            ColumnMap[] baseTypeColumnMaps = null;
+            foreach (EntityType entityType in mappedEntityTypes)
+            {                
+                ColumnMap[] propertyColumnMaps = GetColumnMapsForType(storeDataReader, entityType, resultMapping.ReturnTypeColumnsRenameMapping);
+                EntityColumnMap entityColumnMap = CreateEntityTypeElementColumnMap(storeDataReader, entityType, entitySet, propertyColumnMaps, resultMapping.ReturnTypeColumnsRenameMapping);
+                if (!entityType.Abstract)
+                {
+                    typeChoices.Add(entityType, entityColumnMap);
+                }
+                if (entityType == baseStructuralType)
+                {
+                    baseTypeColumnMaps = propertyColumnMaps;
+                }
+            }
+
+            // NOTE: We don't have a null sentinel here, because the stored proc won't 
+            //       return one anyway; we'll just presume the data's always there.
+            MultipleDiscriminatorPolymorphicColumnMap polymorphicMap = new MultipleDiscriminatorPolymorphicColumnMap(TypeUsage.Create(baseStructuralType), baseStructuralType.Name, baseTypeColumnMaps, discriminatorColumns, typeChoices, (object[] discriminatorValues) => mapping.Discriminate(discriminatorValues, resultSetIndex));
+            CollectionColumnMap collection = new SimpleCollectionColumnMap(baseStructuralType.GetCollectionType().TypeUsage, baseStructuralType.Name, polymorphicMap, null, null);
+            return collection;
+        }
+
+        /// <summary>
+        /// Build the collectionColumnMap from a store datareader, a type and an entitySet.
+        /// </summary>
+        /// <param name="storeDataReader"></param>
+        /// <param name="edmType"></param>
+        /// <param name="entitySet"></param>
+        /// <returns></returns>
+        internal static CollectionColumnMap CreateColumnMapFromReaderAndType(DbDataReader storeDataReader, EdmType edmType, EntitySet entitySet, Dictionary<string, FunctionImportReturnTypeStructuralTypeColumnRenameMapping> renameList)
+        {
+            Debug.Assert(Helper.IsEntityType(edmType) || null == entitySet, "The specified non-null EntitySet is incompatible with the EDM type specified.");
+
+            // Next, build the ColumnMap directly from the edmType and entitySet provided.
+            ColumnMap[] propertyColumnMaps = GetColumnMapsForType(storeDataReader, edmType, renameList);
+            ColumnMap elementColumnMap = null;
+
+            // NOTE: We don't have a null sentinel here, because the stored proc won't 
+            //       return one anyway; we'll just presume the data's always there.
+            if (Helper.IsRowType(edmType))
+            {
+                elementColumnMap = new RecordColumnMap(TypeUsage.Create(edmType), edmType.Name, propertyColumnMaps, null);
+            }
+            else if (Helper.IsComplexType(edmType))
+            {
+                elementColumnMap = new ComplexTypeColumnMap(TypeUsage.Create(edmType), edmType.Name, propertyColumnMaps, null);
+            }
+            else if (Helper.IsScalarType(edmType))
+            {
+                if (storeDataReader.FieldCount != 1)
+                {
+                    throw EntityUtil.CommandExecutionDataReaderFieldCountForScalarType();
+                }
+                elementColumnMap = new ScalarColumnMap(TypeUsage.Create(edmType), edmType.Name, 0, 0);
+            }
+            else if (Helper.IsEntityType(edmType))
+            {
+                elementColumnMap = CreateEntityTypeElementColumnMap(storeDataReader, edmType, entitySet, propertyColumnMaps, null/*renameList*/);
+            }
+            else
+            {
+                Debug.Assert(false, "unexpected edmType?");
+            }
+            CollectionColumnMap collection = new SimpleCollectionColumnMap(edmType.GetCollectionType().TypeUsage, edmType.Name, elementColumnMap, null, null);
+            return collection;
+        }
+
+        /// <summary>
+        /// Requires: a public type with a public, default constructor. Returns a column map initializing the type
+        /// and all properties of the type with a public setter taking a primitive type and having a corresponding 
+        /// column in the reader.
+        /// </summary>
+        internal static CollectionColumnMap CreateColumnMapFromReaderAndClrType(DbDataReader reader, Type type, MetadataWorkspace workspace)
+        {
+            Debug.Assert(null != reader);
+            Debug.Assert(null != type);
+            Debug.Assert(null != workspace);
+
+            // we require a default constructor
+            ConstructorInfo constructor = type.GetConstructor(BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance,
+                null, Type.EmptyTypes, null);
+            if (type.IsAbstract || (null == constructor && !type.IsValueType))
+            {
+                throw EntityUtil.InvalidOperation(
+                    Strings.ObjectContext_InvalidTypeForStoreQuery(type));
+            }
+
+            // build a LINQ expression used by result assembly to create results
+            var memberInfo = new List<Tuple<MemberAssignment, int, EdmProperty>>();
+            foreach (PropertyInfo prop in type.GetProperties(BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance))
+            {
+                // for enums unwrap the type if nullable
+                var propertyUnderlyingType = Nullable.GetUnderlyingType(prop.PropertyType) ?? prop.PropertyType;
+                Type propType = propertyUnderlyingType.IsEnum ? propertyUnderlyingType.GetEnumUnderlyingType() : prop.PropertyType;
+
+                EdmType modelType;
+                int ordinal;
+                if (TryGetColumnOrdinalFromReader(reader, prop.Name, out ordinal) &&
+                    MetadataHelper.TryDetermineCSpaceModelType(propType, workspace, out modelType) &&
+                    (Helper.IsScalarType(modelType)) &&
+                    prop.CanWrite && prop.GetIndexParameters().Length == 0 && null != prop.GetSetMethod(/* nonPublic */true))
+                {
+                    memberInfo.Add(Tuple.Create(
+                        Expression.Bind(prop, Expression.Parameter(prop.PropertyType, "placeholder")),
+                        ordinal,
+                        new EdmProperty(prop.Name, TypeUsage.Create(modelType))));
+                }
+            }
+            // initialize members in the order in which they appear in the reader
+            MemberInfo[] members = new MemberInfo[memberInfo.Count];
+            MemberBinding[] memberBindings = new MemberBinding[memberInfo.Count];
+            ColumnMap[] propertyMaps = new ColumnMap[memberInfo.Count];
+            EdmProperty[] modelProperties = new EdmProperty[memberInfo.Count];
+            int i = 0;
+            foreach (var memberGroup in memberInfo.GroupBy(tuple => tuple.Item2).OrderBy(tuple => tuple.Key))
+            {
+                // make sure that a single column isn't contributing to multiple properties
+                if (memberGroup.Count() != 1)
+                {
+                    throw EntityUtil.InvalidOperation(Strings.ObjectContext_TwoPropertiesMappedToSameColumn(
+                        reader.GetName(memberGroup.Key), 
+                        String.Join(", ", memberGroup.Select(tuple => tuple.Item3.Name).ToArray())));
+                }
+
+                var member = memberGroup.Single();
+                MemberAssignment assignment = member.Item1;
+                int ordinal = member.Item2;
+                EdmProperty modelProp = member.Item3;
+                
+                members[i] = assignment.Member;
+                memberBindings[i] = assignment;
+                propertyMaps[i] = new ScalarColumnMap(modelProp.TypeUsage, modelProp.Name, 0, ordinal);
+                modelProperties[i] = modelProp;
+                i++;
+            }
+            NewExpression newExpr = null == constructor ? Expression.New(type) : Expression.New(constructor);
+            MemberInitExpression init = Expression.MemberInit(newExpr, memberBindings);
+            InitializerMetadata initMetadata = InitializerMetadata.CreateProjectionInitializer(
+                (EdmItemCollection)workspace.GetItemCollection(DataSpace.CSpace), init, members);
+
+            // column map (a collection of rows with InitializerMetadata markup)
+            RowType rowType = new RowType(modelProperties, initMetadata);
+            RecordColumnMap rowMap = new RecordColumnMap(TypeUsage.Create(rowType),
+                "DefaultTypeProjection", propertyMaps, null);
+            CollectionColumnMap collectionMap = new SimpleCollectionColumnMap(rowType.GetCollectionType().TypeUsage, 
+                rowType.Name, rowMap, null, null);
+            return collectionMap;
+        }
+
+        /// <summary>
+        /// Build the entityColumnMap from a store datareader, a type and an entitySet and 
+        /// a list ofproperties.
+        /// </summary>
+        /// <param name="storeDataReader"></param>
+        /// <param name="edmType"></param>
+        /// <param name="entitySet"></param>
+        /// <param name="propertyColumnMaps"></param>
+        /// <returns></returns>
+        private static EntityColumnMap CreateEntityTypeElementColumnMap(
+            DbDataReader storeDataReader, EdmType edmType, EntitySet entitySet,
+            ColumnMap[] propertyColumnMaps, Dictionary<string, FunctionImportReturnTypeStructuralTypeColumnRenameMapping> renameList)
+        {
+            EntityType entityType = (EntityType)edmType;
+
+            // The tricky part here is
+            // that the KeyColumns list must point at the same ColumnMap(s) that 
+            // the properties list points to, so we build a quick array of 
+            // ColumnMap(s) that are indexed by their ordinal; then we can walk
+            // the list of keyMembers, and find the ordinal in the reader, and 
+            // pick the same ColumnMap for it.
+
+            // Build the ordinal -> ColumnMap index
+            ColumnMap[] ordinalToColumnMap = new ColumnMap[storeDataReader.FieldCount];
+
+            foreach (ColumnMap propertyColumnMap in propertyColumnMaps)
+            {
+                int ordinal = ((ScalarColumnMap)propertyColumnMap).ColumnPos;
+                ordinalToColumnMap[ordinal] = propertyColumnMap;
+            }
+
+            // Now build the list of KeyColumns;
+            IList<EdmMember> keyMembers = entityType.KeyMembers;
+            SimpleColumnMap[] keyColumns = new SimpleColumnMap[keyMembers.Count];
+
+            int keyMemberIndex = 0;
+            foreach (EdmMember keyMember in keyMembers)
+            {
+                int keyOrdinal = GetMemberOrdinalFromReader(storeDataReader, keyMember, edmType, renameList);
+
+                Debug.Assert(keyOrdinal >= 0, "keyMember for entity is not found by name in the data reader?");
+
+                ColumnMap keyColumnMap = ordinalToColumnMap[keyOrdinal];
+
+                Debug.Assert(null != keyColumnMap, "keyMember for entity isn't in properties collection for the entity?");
+                keyColumns[keyMemberIndex] = (SimpleColumnMap)keyColumnMap;
+                keyMemberIndex++;
+            }
+
+            SimpleEntityIdentity entityIdentity = new SimpleEntityIdentity(entitySet, keyColumns);
+
+            EntityColumnMap result = new EntityColumnMap(TypeUsage.Create(edmType), edmType.Name, propertyColumnMaps, entityIdentity);
+            return result;
+        }
+
+        /// <summary>
+        /// For a given edmType, build an array of scalarColumnMaps that map to the columns
+        /// in the store datareader provided.  Note that we're hooking things up by name, not
+        /// by ordinal position.
+        /// </summary>
+        /// <param name="storeDataReader"></param>
+        /// <param name="edmType"></param>
+        /// <returns></returns>
+        private static ColumnMap[] GetColumnMapsForType(DbDataReader storeDataReader, EdmType edmType, Dictionary<string, FunctionImportReturnTypeStructuralTypeColumnRenameMapping> renameList)
+        {
+            // First get the list of properties; NOTE: we need to hook up the column by name, 
+            // not by position.
+            IBaseList<EdmMember> members = TypeHelpers.GetAllStructuralMembers(edmType);
+            ColumnMap[] propertyColumnMaps = new ColumnMap[members.Count];
+
+            int index = 0;
+            foreach (EdmMember member in members)
+            {
+                if (!Helper.IsScalarType(member.TypeUsage.EdmType))
+                {
+                    throw EntityUtil.InvalidOperation(Strings.ADP_InvalidDataReaderUnableToMaterializeNonScalarType(member.Name, member.TypeUsage.EdmType.FullName));
+                }
+
+                int ordinal = GetMemberOrdinalFromReader(storeDataReader, member, edmType, renameList);
+
+                propertyColumnMaps[index] = new ScalarColumnMap(member.TypeUsage, member.Name, 0, ordinal);
+                index++;
+            }
+            return propertyColumnMaps;
+        }
+
+        private static ScalarColumnMap[] CreateDiscriminatorColumnMaps(DbDataReader storeDataReader, FunctionImportMappingNonComposable mapping, int resultIndex)
+        {
+            // choose an arbitrary type for discriminator columns -- the type is not
+            // actually statically known
+            EdmType discriminatorType =
+                MetadataItem.EdmProviderManifest.GetPrimitiveType(PrimitiveTypeKind.String);
+            TypeUsage discriminatorTypeUsage =
+                TypeUsage.Create(discriminatorType);
+
+            IList<string> discriminatorColumnNames = mapping.GetDiscriminatorColumns(resultIndex);
+            ScalarColumnMap[] discriminatorColumns = new ScalarColumnMap[discriminatorColumnNames.Count];
+            for (int i = 0; i < discriminatorColumns.Length; i++)
+            {
+                string columnName = discriminatorColumnNames[i];
+                ScalarColumnMap columnMap = new ScalarColumnMap(discriminatorTypeUsage, columnName, 0,
+                    GetDiscriminatorOrdinalFromReader(storeDataReader, columnName, mapping.FunctionImport));
+                discriminatorColumns[i] = columnMap;
+            }
+            return discriminatorColumns;
+        }
+
+        /// <summary>
+        /// Given a store datareader and a member of an edmType, find the column ordinal
+        /// in the datareader with the name of the member.
+        /// </summary>
+        /// <param name="storeDataReader"></param>
+        /// <param name="member"></param>
+        /// <returns></returns>
+        private static int GetMemberOrdinalFromReader(DbDataReader storeDataReader, EdmMember member, EdmType currentType, Dictionary<string, FunctionImportReturnTypeStructuralTypeColumnRenameMapping> renameList)
+        {
+            int result;
+            string memberName = GetRenameForMember(member, currentType, renameList);
+
+            if (!TryGetColumnOrdinalFromReader(storeDataReader, memberName, out result))
+            {
+                throw EntityUtil.CommandExecutionDataReaderMissingColumnForType(member, currentType);
+            }
+            return result;
+        }
+
+        private static string GetRenameForMember(EdmMember member, EdmType currentType, Dictionary<string, FunctionImportReturnTypeStructuralTypeColumnRenameMapping> renameList)
+        {
+            // if list is null,
+            // or no rename mapping at all,
+            // or partial rename and the member is not specified by the renaming
+            // then we return the original member.Name
+            // otherwise we return the mapped one
+            return renameList == null || renameList.Count == 0 || !renameList.Any(m => m.Key == member.Name) ? member.Name : renameList[member.Name].GetRename(currentType);
+        }
+
+        /// <summary>
+        /// Given a store datareader, a column name, find the column ordinal
+        /// in the datareader with the name of the column.
+        /// 
+        /// We only have the functionImport provided to include it in the exception 
+        /// message.
+        /// </summary>
+        /// <param name="storeDataReader"></param>
+        /// <param name="columnName"></param>
+        /// <param name="functionImport"></param>
+        /// <returns></returns>
+        private static int GetDiscriminatorOrdinalFromReader(DbDataReader storeDataReader, string columnName, EdmFunction functionImport)
+        {
+            int result;
+            if (!TryGetColumnOrdinalFromReader(storeDataReader, columnName, out result))
+            {
+                throw EntityUtil.CommandExecutionDataReaderMissinDiscriminatorColumn(columnName, functionImport);
+            }
+            return result;
+        }
+
+        /// <summary>
+        /// Given a store datareader and a column name, try to find the column ordinal
+        /// in the datareader with the name of the column.
+        /// </summary>
+        /// <param name="storeDataReader"></param>
+        /// <param name="columnName"></param>
+        /// <param name="ordinal"></param>
+        /// <returns>true if found, false otherwise.</returns>
+        private static bool TryGetColumnOrdinalFromReader(DbDataReader storeDataReader, string columnName, out int ordinal)
+        {
+            if (0 == storeDataReader.FieldCount)
+            {
+                // If there are no fields, there can't be a match (this check avoids
+                // an InvalidOperationException on the call to GetOrdinal)
+                ordinal = default(int);
+                return false;
+            }
+
+            // Wrap ordinal lookup for the member so that we can throw a nice exception.
+            try
+            {
+                ordinal = storeDataReader.GetOrdinal(columnName);
+                return true;
+            }
+            catch (IndexOutOfRangeException)
+            {
+                // No column matching the column name found
+                ordinal = default(int);
+                return false;
+            }
+        }
+    }
+}

mcs/class/referencesource/System.Data.Entity/System/Data/Query/InternalTrees/ColumnMapVisitor.cs

@@ -0,0 +1,258 @@
+//---------------------------------------------------------------------
+// <copyright file="ColumnMapVisitorWithResults.cs" company="Microsoft">
+//      Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//
+// @owner  [....]
+// @backupOwner [....]
+//---------------------------------------------------------------------
+
+namespace System.Data.Query.InternalTrees
+{
+    using System.Collections;
+    using System.Collections.Generic;
+    using System.Text;
+    using System.Data;
+    using System.Data.Common;
+    using System.Data.Common.CommandTrees;
+    using System.Data.Metadata.Edm;
+    using System.Data.Query.PlanCompiler;
+    using System.Diagnostics;
+    using System.IO;
+    using System.Threading;
+
+    /// <summary>
+    /// Basic Visitor Design Pattern support for ColumnMap hierarchy;
+    /// 
+    /// This visitor class will walk the entire hierarchy, but does not
+    /// return results; it's useful for operations such as printing and
+    /// searching.
+    /// </summary>
+    /// <typeparam name="TArgType"></typeparam>
+    internal abstract class ColumnMapVisitor<TArgType>
+    {
+        #region visitor helpers
+
+        /// <summary>
+        /// Common List(ColumnMap) code
+        /// </summary>
+        /// <param name="columnMaps"></param>
+        /// <param name="arg"></param>
+        protected void VisitList<TListType>(TListType[] columnMaps, TArgType arg)
+                   where TListType : ColumnMap
+        {
+            foreach (TListType columnMap in columnMaps)
+            {
+                columnMap.Accept(this, arg);
+            }
+        }
+
+        #endregion
+
+        #region EntityIdentity handling
+
+        protected void VisitEntityIdentity(EntityIdentity entityIdentity, TArgType arg)
+        {
+            DiscriminatedEntityIdentity dei = entityIdentity as DiscriminatedEntityIdentity;
+            if (null != dei)
+            {
+                VisitEntityIdentity(dei, arg);
+            }
+            else
+            {
+                VisitEntityIdentity((SimpleEntityIdentity)entityIdentity, arg);
+            }
+        }
+
+        protected virtual void VisitEntityIdentity(DiscriminatedEntityIdentity entityIdentity, TArgType arg)
+        {
+            entityIdentity.EntitySetColumnMap.Accept(this, arg);
+            foreach (SimpleColumnMap columnMap in entityIdentity.Keys)
+            {
+                columnMap.Accept(this, arg);
+            }
+        }
+
+        protected virtual void VisitEntityIdentity(SimpleEntityIdentity entityIdentity, TArgType arg)
+        {
+            foreach (SimpleColumnMap columnMap in entityIdentity.Keys)
+            {
+                columnMap.Accept(this, arg);
+            }
+        }
+
+        #endregion
+
+        #region Visitor methods
+
+        internal virtual void Visit(ComplexTypeColumnMap columnMap, TArgType arg)
+        {
+            ColumnMap nullSentinel = columnMap.NullSentinel;
+            if (null != nullSentinel) 
+            {
+                nullSentinel.Accept(this, arg);
+            }
+            foreach (ColumnMap p in columnMap.Properties)
+            {
+                p.Accept(this, arg);
+            }
+        }
+
+        internal virtual void Visit(DiscriminatedCollectionColumnMap columnMap, TArgType arg)
+        {
+            columnMap.Discriminator.Accept(this, arg);
+            foreach (SimpleColumnMap fk in columnMap.ForeignKeys)
+            {
+                fk.Accept(this, arg);
+            }
+            foreach (SimpleColumnMap k in columnMap.Keys)
+            {
+                k.Accept(this, arg);
+            }
+            columnMap.Element.Accept(this, arg);
+        }
+
+        internal virtual void Visit(EntityColumnMap columnMap, TArgType arg)
+        {
+            VisitEntityIdentity(columnMap.EntityIdentity, arg);
+            foreach (ColumnMap p in columnMap.Properties)
+            {
+                p.Accept(this, arg);
+            }
+        }
+
+        internal virtual void Visit(SimplePolymorphicColumnMap columnMap, TArgType arg)
+        {
+            columnMap.TypeDiscriminator.Accept(this, arg);
+            foreach (ColumnMap cm in columnMap.TypeChoices.Values)
+            {
+                cm.Accept(this, arg);
+            }
+            foreach (ColumnMap p in columnMap.Properties)
+            {
+                p.Accept(this, arg);
+            }
+        }
+
+        internal virtual void Visit(MultipleDiscriminatorPolymorphicColumnMap columnMap, TArgType arg)
+        {
+            foreach (var typeDiscriminator in columnMap.TypeDiscriminators)
+            {
+                typeDiscriminator.Accept(this, arg);
+            }
+            foreach (var typeColumnMap in columnMap.TypeChoices.Values)
+            {
+                typeColumnMap.Accept(this, arg);
+            }
+            foreach (var property in columnMap.Properties)
+            {
+                property.Accept(this, arg);
+            }
+        }
+
+        internal virtual void Visit(RecordColumnMap columnMap, TArgType arg)
+        {
+            ColumnMap nullSentinel = columnMap.NullSentinel;
+            if (null != nullSentinel) 
+            {
+                nullSentinel.Accept(this, arg);
+            }
+            foreach (ColumnMap p in columnMap.Properties)
+            {
+                p.Accept(this, arg);
+            }
+        }
+
+        internal virtual void Visit(RefColumnMap columnMap, TArgType arg)
+        {
+            VisitEntityIdentity(columnMap.EntityIdentity, arg);
+        }
+
+        internal virtual void Visit(ScalarColumnMap columnMap, TArgType arg)
+        {
+        }
+
+        internal virtual void Visit(SimpleCollectionColumnMap columnMap, TArgType arg)
+        {
+            foreach (SimpleColumnMap fk in columnMap.ForeignKeys)
+            {
+                fk.Accept(this, arg);
+            }
+            foreach (SimpleColumnMap k in columnMap.Keys)
+            {
+                k.Accept(this, arg);
+            }
+            columnMap.Element.Accept(this, arg);
+        }
+
+        internal virtual void Visit(VarRefColumnMap columnMap, TArgType arg)
+        {
+        }
+
+        #endregion
+    }
+
+    /// <summary>
+    /// Basic Visitor Design Pattern support for ColumnMap hierarchy; 
+    /// 
+    /// This visitor class allows you to return results; it's useful for operations
+    /// that copy or manipulate the hierarchy.
+    /// </summary>
+    /// <typeparam name="TArgType"></typeparam>
+    /// <typeparam name="TResultType"></typeparam>
+    internal abstract class ColumnMapVisitorWithResults<TResultType, TArgType>
+    {
+
+        #region EntityIdentity handling
+
+        protected EntityIdentity VisitEntityIdentity(EntityIdentity entityIdentity, TArgType arg)
+        {
+            DiscriminatedEntityIdentity dei = entityIdentity as DiscriminatedEntityIdentity;
+            if (null != dei)
+            {
+                return VisitEntityIdentity(dei, arg);
+            }
+            else
+            {
+                return VisitEntityIdentity((SimpleEntityIdentity)entityIdentity, arg);
+            }
+        }
+
+        protected virtual EntityIdentity VisitEntityIdentity(DiscriminatedEntityIdentity entityIdentity, TArgType arg)
+        {
+            return entityIdentity;
+        }
+
+        protected virtual EntityIdentity VisitEntityIdentity(SimpleEntityIdentity entityIdentity, TArgType arg)
+        {
+            return entityIdentity;
+        }
+
+        #endregion
+
+        #region Visitor methods
+
+        internal abstract TResultType Visit(ComplexTypeColumnMap columnMap, TArgType arg);
+
+        internal abstract TResultType Visit(DiscriminatedCollectionColumnMap columnMap, TArgType arg);
+
+        internal abstract TResultType Visit(EntityColumnMap columnMap, TArgType arg);
+
+        internal abstract TResultType Visit(SimplePolymorphicColumnMap columnMap, TArgType arg);
+
+        internal abstract TResultType Visit(RecordColumnMap columnMap, TArgType arg);
+
+        internal abstract TResultType Visit(RefColumnMap columnMap, TArgType arg);
+
+        internal abstract TResultType Visit(ScalarColumnMap columnMap, TArgType arg);
+
+        internal abstract TResultType Visit(SimpleCollectionColumnMap columnMap, TArgType arg);
+
+        internal abstract TResultType Visit(VarRefColumnMap columnMap, TArgType arg);
+
+        internal abstract TResultType Visit(MultipleDiscriminatorPolymorphicColumnMap columnMap, TArgType arg);
+
+        #endregion
+    }
+
+}

mcs/class/referencesource/System.Data.Entity/System/Data/Query/InternalTrees/ExplicitDiscriminatorMap.cs

@@ -0,0 +1,81 @@
+//---------------------------------------------------------------------
+// <copyright file="ExplicitDiscriminatorMap.cs" company="Microsoft">
+//      Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//
+// @owner  [....]
+// @backupOwner [....]
+//---------------------------------------------------------------------
+
+using System.Data.Metadata.Edm;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace System.Data.Query.InternalTrees
+{
+    /// <summary>
+    /// Describes user-defined discriminator metadata (e.g. for a basic TPH mapping). Encapsulates
+    /// relevant data from System.Data.Mapping.ViewGenerabetion.DiscriminatorMap (that is to say,
+    /// data relevant to the PlanCompiler). This separate class accomplishes two things:
+    /// 
+    /// 1. Maintain separation of ViewGen and PlanCompiler
+    /// 2. Avoid holding references to CQT expressions in ITree ops (which the ViewGen.DiscriminatorMap
+    /// holds a few CQT references)
+    /// </summary>
+    internal class ExplicitDiscriminatorMap
+    {
+        private readonly System.Collections.ObjectModel.ReadOnlyCollection<KeyValuePair<object, EntityType>> m_typeMap;
+        private readonly EdmMember m_discriminatorProperty;
+        private readonly System.Collections.ObjectModel.ReadOnlyCollection<EdmProperty> m_properties;
+
+        internal ExplicitDiscriminatorMap(System.Data.Mapping.ViewGeneration.DiscriminatorMap template)
+        {
+            m_typeMap = template.TypeMap;
+            m_discriminatorProperty = template.Discriminator.Property;
+            m_properties = template.PropertyMap.Select(propertyValuePair => propertyValuePair.Key)
+                .ToList().AsReadOnly();
+        }
+
+        /// <summary>
+        /// Maps from discriminator value to type.
+        /// </summary>
+        internal System.Collections.ObjectModel.ReadOnlyCollection<KeyValuePair<object, EntityType>> TypeMap
+        {
+            get { return m_typeMap; }
+        }
+
+        /// <summary>
+        /// Gets property containing discriminator value.
+        /// </summary>
+        internal EdmMember DiscriminatorProperty
+        {
+            get { return m_discriminatorProperty; }
+        }
+
+
+        /// <summary>
+        /// All properties for the type hierarchy.
+        /// </summary>
+        internal System.Collections.ObjectModel.ReadOnlyCollection<EdmProperty> Properties
+        {
+            get { return m_properties; }
+        }
+
+        /// <summary>
+        /// Returns the type id for the given entity type, or null if non exists.
+        /// </summary>
+        internal object GetTypeId(EntityType entityType)
+        {
+            object result = null;
+            foreach (var discriminatorTypePair in this.TypeMap)
+            {
+                if (discriminatorTypePair.Value.EdmEquals(entityType))
+                {
+                    result = discriminatorTypePair.Key;
+                    break;
+                }
+            }
+            return result;
+        }
+    }
+}

mcs/class/referencesource/System.Data.Entity/System/Data/Query/InternalTrees/Metadata.cs

@@ -0,0 +1,271 @@
+//---------------------------------------------------------------------
+// <copyright file="Metadata.cs" company="Microsoft">
+//      Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//
+// @owner  [....]
+// @backupOwner [....]
+//---------------------------------------------------------------------
+
+using System;
+using System.Collections.Generic;
+using System.Data.Common;
+using System.Data.Metadata.Edm;
+using System.Globalization;
+using System.Diagnostics;
+
+namespace System.Data.Query.InternalTrees
+{
+    /// <summary>
+    /// Describes metadata about a table
+    /// </summary>
+    internal class TableMD
+    {
+        private List<ColumnMD> m_columns;
+        private List<ColumnMD> m_keys;
+
+        private EntitySetBase m_extent; // null for transient tables
+        private bool m_flattened;
+
+        /// <summary>
+        /// private initializer
+        /// </summary>
+        /// <param name="extent">the entity set corresponding to this table (if any)</param>
+        private TableMD(EntitySetBase extent)
+        {
+            m_columns = new List<ColumnMD>();
+            m_keys = new List<ColumnMD>();
+            m_extent = extent;
+        }
+
+        /// <summary>
+        /// Create a typed-table definition corresponding to an entityset (if specified)
+        /// 
+        /// The table has exactly one column - the type of the column is specified by 
+        /// the "type" parameter. This table is considered to be un-"flattened"
+        /// </summary>
+        /// <param name="type">type of each element (row) of the table</param>
+        /// <param name="extent">entityset corresponding to the table (if any)</param>
+        internal TableMD(TypeUsage type, EntitySetBase extent)
+            : this(extent)
+        {
+            m_columns.Add(new ColumnMD(this, "element", type));
+            m_flattened = !PlanCompiler.TypeUtils.IsStructuredType(type);
+        }
+
+        /// <summary>
+        /// Creates a "flattened" table definition. 
+        /// 
+        /// The table has one column for each specified property in the "properties" parameter. 
+        /// The name and datatype of each table column are taken from the corresponding property.
+        /// 
+        /// The keys of the table (if any) are those specified in the "keyProperties" parameter
+        /// 
+        /// The table may correspond to an entity set (if the entityset parameter was non-null)
+        /// </summary>
+        /// <param name="properties">prperties corresponding to columns of the table</param>
+        /// <param name="keyProperties"></param>
+        /// <param name="extent">entityset corresponding to the table (if any)</param>
+        internal TableMD(IEnumerable<EdmProperty> properties, IEnumerable<EdmMember> keyProperties,
+            EntitySetBase extent)
+            : this(extent)
+        {
+            Dictionary<string, ColumnMD> columnMap = new Dictionary<string, ColumnMD>();
+            m_flattened = true;
+
+            foreach (EdmProperty p in properties)
+            {
+                ColumnMD newColumn = new ColumnMD(this, p);
+                m_columns.Add(newColumn);
+                columnMap[p.Name] = newColumn;
+            }
+            foreach (EdmMember p in keyProperties)
+            {
+                ColumnMD keyColumn;
+                if (!columnMap.TryGetValue(p.Name, out keyColumn))
+                {
+                    Debug.Assert(false, "keyMember not in columns?");
+                }
+                else
+                {
+                    m_keys.Add(keyColumn);
+                }
+            }
+        }
+
+        /// <summary>
+        /// The extent metadata (if any)
+        /// </summary>
+        internal EntitySetBase Extent { get { return m_extent; } }
+
+        /// <summary>
+        /// List of columns of this table
+        /// </summary>
+        internal List<ColumnMD> Columns { get { return m_columns; } }
+
+        /// <summary>
+        /// Keys for this table
+        /// </summary>
+        internal List<ColumnMD> Keys { get { return m_keys; } }
+
+        /// <summary>
+        /// Is this table a "flat" table?
+        /// </summary>
+        internal bool Flattened { get { return m_flattened; } }
+
+        /// <summary>
+        /// String form - for debugging
+        /// </summary>
+        /// <returns></returns>
+        public override string ToString()
+        {
+            return (m_extent != null ? m_extent.Name : "Transient");
+        }
+    }
+
+    /// <summary>
+    /// Describes information about each column
+    /// </summary>
+    internal class ColumnMD
+    {
+        private string m_name;
+        private TypeUsage m_type;
+        private EdmMember m_property;
+
+        /// <summary>
+        /// Default constructor
+        /// </summary>
+        /// <param name="table">Table containing this column</param>
+        /// <param name="name">Column name</param>
+        /// <param name="type">Datatype of the column</param>
+        internal ColumnMD(TableMD table, string name, TypeUsage type)
+        {
+            m_name = name;
+            m_type = type;
+        }
+
+        /// <summary>
+        /// More useful default constructor
+        /// </summary>
+        /// <param name="table">table containing this column</param>
+        /// <param name="property">property describing this column</param>
+        internal ColumnMD(TableMD table, EdmMember property)
+            : this(table, property.Name, property.TypeUsage)
+        {
+            m_property = property;
+        }
+
+        /// <summary>
+        /// Column Name
+        /// </summary>
+        internal string Name { get { return m_name; } }
+
+        /// <summary>
+        /// Datatype of the column
+        /// </summary>
+        internal TypeUsage Type { get { return m_type; } }
+
+        /// <summary>
+        /// Is this column nullable ?
+        /// </summary>
+        internal bool IsNullable 
+        {
+            get
+            {
+                return (m_property == null) || TypeSemantics.IsNullable(m_property);
+            }
+        }
+
+        /// <summary>
+        /// debugging help
+        /// </summary>
+        /// <returns></returns>
+        public override string ToString()
+        {
+            return m_name;
+        }
+    }
+
+    /// <summary>
+    /// Represents one instance of a table. Contains the table metadata
+    /// </summary>
+    internal class Table
+    {
+        private TableMD m_tableMetadata;
+        private VarList m_columns;
+        private VarVec m_referencedColumns;
+        private VarVec m_keys;
+        private VarVec m_nonnullableColumns;
+        private int m_tableId;
+
+        internal Table(Command command, TableMD tableMetadata, int tableId)
+        {
+            m_tableMetadata = tableMetadata;
+            m_columns = Command.CreateVarList();
+            m_keys = command.CreateVarVec();
+            m_nonnullableColumns = command.CreateVarVec();
+            m_tableId = tableId;
+
+            Dictionary<string, ColumnVar> columnVarMap = new Dictionary<string, ColumnVar>();
+            foreach (ColumnMD c in tableMetadata.Columns)
+            {
+                ColumnVar v = command.CreateColumnVar(this, c);
+                columnVarMap[c.Name] = v;
+                if (!c.IsNullable)
+                {
+                    m_nonnullableColumns.Set(v);
+                }
+            }
+
+            foreach (ColumnMD c in tableMetadata.Keys)
+            {
+                ColumnVar v = columnVarMap[c.Name];
+                m_keys.Set(v);
+            }
+
+            m_referencedColumns = command.CreateVarVec(m_columns);
+        }
+
+        /// <summary>
+        /// Metadata for the table instance
+        /// </summary>
+        internal TableMD TableMetadata { get { return m_tableMetadata; } }
+
+        /// <summary>
+        /// List of column references
+        /// </summary>
+        internal VarList Columns { get { return m_columns; } }
+
+        /// <summary>
+        /// Get the list of all referenced columns. 
+        /// </summary>
+        internal VarVec ReferencedColumns
+        {
+            get { return m_referencedColumns; }
+        }
+
+        /// <summary>
+        /// 
+        /// </summary>
+        internal VarVec NonNullableColumns { get { return m_nonnullableColumns; } }
+
+        /// <summary>
+        /// List of keys
+        /// </summary>
+        internal VarVec Keys { get { return m_keys; } }
+
+        /// <summary>
+        /// (internal) id for this table instance
+        /// </summary>
+        internal int TableId { get { return m_tableId; } }
+
+        /// <summary>
+        /// String form - for debugging
+        /// </summary>
+        /// <returns></returns>
+        public override string ToString()
+        {
+            return String.Format(CultureInfo.InvariantCulture, "{0}::{1}", m_tableMetadata.ToString(), this.TableId); ;
+        }
+    }
+}

mcs/class/referencesource/System.Data.Entity/System/Data/Query/InternalTrees/NodeCounter.cs

@@ -0,0 +1,53 @@
+//---------------------------------------------------------------------
+// <copyright file="NodeCounter.cs" company="Microsoft">
+//      Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//
+// @owner  [....]
+// @backupOwner [....]
+//---------------------------------------------------------------------
+
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.Diagnostics;
+using System.Data.Common;
+using md=System.Data.Metadata.Edm;
+
+namespace System.Data.Query.InternalTrees
+{
+    /// <summary>
+    /// Counts the number of nodes in a tree
+    /// </summary>
+    internal class NodeCounter : BasicOpVisitorOfT<int>
+    {
+        /// <summary>
+        /// Public entry point - Calculates the nubmer of nodes in the given subTree
+        /// </summary>
+        /// <param name="subTree"></param>
+        /// <returns></returns>
+        internal static int Count(Node subTree)
+        {
+            NodeCounter counter = new NodeCounter();
+            return counter.VisitNode(subTree);
+        }
+
+        /// <summary>
+        /// Common processing for all node types
+        /// Count = 1 (self) + count of children
+        /// </summary>
+        /// <param name="n"></param>
+        /// <returns></returns>
+        protected override int VisitDefault(Node n)
+        {
+            int count = 1;
+            foreach (Node child in n.Children)
+            {
+                count += VisitNode(child);
+            }
+            return count;
+        }
+    }
+}
+
+

mcs/class/referencesource/System.Data.Entity/System/Data/Query/InternalTrees/Nodes.cs

@@ -0,0 +1,190 @@
+//---------------------------------------------------------------------
+// <copyright file="Nodes.cs" company="Microsoft">
+//      Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//
+// @owner  [....]
+// @backupOwner [....]
+//---------------------------------------------------------------------
+
+using System;
+using System.Collections.Generic;
+using System.Data.Metadata.Edm;
+using System.Globalization;
+using System.Diagnostics;
+
+namespace System.Data.Query.InternalTrees
+{
+    /// <summary>
+    /// A Node describes a node in a query tree. Each node has an operator, and
+    /// a list of zero or more children of that operator.
+    /// </summary>
+    internal class Node
+    {
+        #region private state
+        private int m_id;
+        private List<Node> m_children;
+        private Op m_op;
+        private NodeInfo m_nodeInfo;
+        #endregion
+
+        #region constructors
+        /// <summary>
+        /// Basic constructor. 
+        /// 
+        /// NEVER call this routine directly - you should always use the Command.CreateNode
+        /// factory methods.
+        /// </summary>
+        /// <param name="nodeId">id for the node</param>
+        /// <param name="op">The operator</param>
+        /// <param name="children">List of child nodes</param>
+        internal Node(int nodeId, Op op, List<Node> children)
+        {
+            m_id = nodeId;
+            m_op = op;
+            m_children = children;
+        }
+
+        /// <summary>
+        /// This routine is only used for building up rule patterns. 
+        /// NEVER use this routine for building up nodes in a user command tree.
+        /// </summary>
+        /// <param name="op"></param>
+        /// <param name="children"></param>
+        internal Node(Op op, params Node[] children)
+            : this(-1, op, new List<Node>(children))
+        {
+        }
+        #endregion
+
+        #region public properties and methods
+
+#if DEBUG
+        internal int Id { get { return m_id; } }
+#endif
+
+        /// <summary>
+        /// Get the list of children
+        /// </summary>
+        internal List<Node> Children { get { return m_children; } }
+
+        /// <summary>
+        /// Gets or sets the node's operator
+        /// </summary>
+        internal Op Op { get { return m_op; } set { m_op = value; } }
+
+        /// <summary>
+        /// Simpler (?) getter/setter routines
+        /// </summary>
+        internal Node Child0 { get { return m_children[0]; } set { m_children[0] = value; } }
+        /// <summary>
+        /// Do I have a zeroth child?
+        /// </summary>
+        internal bool HasChild0 { get { return m_children.Count > 0; } }
+
+        /// <summary>
+        /// Get/set first child
+        /// </summary>
+        internal Node Child1 { get { return m_children[1]; } set { m_children[1] = value; } }
+        /// <summary>
+        /// Do I have a child1?
+        /// </summary>
+        internal bool HasChild1 { get { return m_children.Count > 1; } }
+
+        /// <summary>
+        /// get/set second child
+        /// </summary>
+        internal Node Child2 { get { return m_children[2]; } set { m_children[2] = value; } }
+        /// <summary>
+        /// get/set second child
+        /// </summary>
+        internal Node Child3 { get { return m_children[3]; } /* commented out because of fxcop - there are no upstream callers -- set { m_children[3] = value; }*/ }
+        /// <summary>
+        /// Do I have a child2 (third child really)
+        /// </summary>
+        internal bool HasChild2 { get { return m_children.Count > 2; } }
+        /// <summary>
+        /// Do I have a child3 (fourth child really)
+        /// </summary>
+        internal bool HasChild3 { get { return m_children.Count > 3; } }
+
+        #region equivalence functions
+        /// <summary>
+        /// Is this subtree equivalent to another subtree
+        /// </summary>
+        /// <param name="other"></param>
+        /// <returns></returns>
+        internal bool IsEquivalent(Node other)
+        {
+            if (this.Children.Count != other.Children.Count)
+            {
+                return false;
+            }
+            bool? opEquivalent = this.Op.IsEquivalent(other.Op);
+            if (opEquivalent != true)
+            {
+                return false;
+            }
+            for (int i = 0; i < this.Children.Count; i++)
+            {
+                if (!this.Children[i].IsEquivalent(other.Children[i]))
+                {
+                    return false;
+                }
+            }
+            return true;
+        }
+        #endregion
+
+        #region NodeInfo methods and properties
+        /// <summary>
+        /// Has the node info been initialized, i.e. previously computed
+        /// </summary>
+        internal bool IsNodeInfoInitialized { get { return (m_nodeInfo != null);  } }
+
+        /// <summary>
+        /// Get the nodeInfo for a node. Initializes it, if it has not yet been initialized
+        /// </summary>
+        /// <param name="command">Current command object</param>
+        /// <returns>NodeInfo for this node</returns>
+        internal NodeInfo GetNodeInfo(Command command)
+        {
+            if (m_nodeInfo == null)
+            {
+                InitializeNodeInfo(command);
+            }
+            return m_nodeInfo;
+        }
+        /// <summary>
+        /// Gets the "extended" nodeinfo for a node; if it has not yet been initialized, then it will be
+        /// </summary>
+        /// <param name="command">current command object</param>
+        /// <returns>extended nodeinfo for this node</returns>
+        internal ExtendedNodeInfo GetExtendedNodeInfo(Command command)
+        {
+            if (m_nodeInfo == null)
+            {
+                InitializeNodeInfo(command);
+            }
+            ExtendedNodeInfo extendedNodeInfo = m_nodeInfo as ExtendedNodeInfo;
+            Debug.Assert(extendedNodeInfo != null);
+            return extendedNodeInfo;
+        }
+
+        private void InitializeNodeInfo(Command command)
+        {
+            if (this.Op.IsRelOp || this.Op.IsPhysicalOp)
+            {
+                m_nodeInfo = new ExtendedNodeInfo(command);
+            }
+            else
+            {
+                m_nodeInfo = new NodeInfo(command);
+            }
+            command.RecomputeNodeInfo(this);
+        }
+        #endregion
+
+        #endregion
+    }
+}

mcs/class/referencesource/System.Data.Entity/System/Data/Query/InternalTrees/PhysicalOps.cs

@@ -0,0 +1,341 @@
+//---------------------------------------------------------------------
+// <copyright file="PhysicalOps.cs" company="Microsoft">
+//      Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//
+// @owner  [....]
+// @backupOwner [....]
+//---------------------------------------------------------------------
+
+using System;
+using System.Collections.Generic;
+using System.Data.Metadata.Edm;
+using System.Diagnostics;
+using System.Globalization;
+using System.Data.Query.PlanCompiler;
+using md = System.Data.Metadata.Edm;
+
+namespace System.Data.Query.InternalTrees
+{
+    /// <summary>
+    /// A PhysicalProjectOp is a physical Op capping the entire command tree (and the 
+    /// subtrees of CollectOps). 
+    /// </summary>
+    internal class PhysicalProjectOp : PhysicalOp
+    {
+        #region public methods
+        /// <summary>
+        /// Instance for pattern matching in rules
+        /// </summary>
+        internal static readonly PhysicalProjectOp Pattern = new PhysicalProjectOp();
+ 
+        /// <summary>
+        /// Get the column map that describes how the result should be reshaped
+        /// </summary>
+        internal SimpleCollectionColumnMap ColumnMap 
+        { 
+            get { return m_columnMap; } 
+        }
+
+        /// <summary>
+        /// Get the (ordered) list of output vars that this node produces
+        /// </summary>
+        internal VarList Outputs 
+        { 
+            get { return m_outputVars; } 
+        }
+
+        /// <summary>
+        /// Visitor pattern method
+        /// </summary>
+        /// <param name="v">The BasicOpVisitor that is visiting this Op</param>
+        /// <param name="n">The Node that references this Op</param>
+        [DebuggerNonUserCode]
+        internal override void Accept(BasicOpVisitor v, Node n) { v.Visit(this, n); }
+
+        /// <summary>
+        /// Visitor pattern method for visitors with a return value
+        /// </summary>
+        /// <param name="v">The visitor</param>
+        /// <param name="n">The node in question</param>
+        /// <returns>An instance of TResultType</returns>
+        [DebuggerNonUserCode]
+        internal override TResultType Accept<TResultType>(BasicOpVisitorOfT<TResultType> v, Node n) { return v.Visit(this, n); }
+
+        #endregion
+
+        #region private constructors
+        /// <summary>
+        /// basic constructor
+        /// </summary>
+        /// <param name="outputVars">List of outputs from this Op</param>
+        /// <param name="columnMap">column map that describes the result to be shaped</param>
+        internal PhysicalProjectOp(VarList outputVars, SimpleCollectionColumnMap columnMap)
+            : this()
+        {
+            Debug.Assert(null != columnMap, "null columnMap?");
+            m_outputVars = outputVars;
+            m_columnMap = columnMap;
+        }
+
+        private PhysicalProjectOp()
+            : base(OpType.PhysicalProject)
+        {
+        }
+        #endregion
+
+        #region private state
+        private SimpleCollectionColumnMap m_columnMap;
+        private VarList m_outputVars;
+        #endregion
+    }
+
+    /// <summary>
+    /// Represents information about one collection being managed by the NestOps. 
+    /// The CollectionVar is a Var that represents the entire collection. 
+    /// </summary>
+    internal class CollectionInfo
+    {
+        #region public methods
+        /// <summary>
+        /// The collection-var
+        /// </summary>
+        internal Var CollectionVar
+        {
+            get { return m_collectionVar; }
+        }
+        /// <summary>
+        /// the column map for the collection element
+        /// </summary>
+        internal ColumnMap ColumnMap
+        {
+            get { return m_columnMap; }
+        }
+
+        /// <summary>
+        /// list of vars describing the collection element; flattened to remove 
+        /// nested collections
+        /// </summary>
+        internal VarList FlattenedElementVars
+        {
+            get { return m_flattenedElementVars; }
+        }
+
+        /// <summary>
+        /// list of keys specific to this collection
+        /// </summary>
+        internal VarVec Keys
+        {
+            get { return m_keys; }
+        }
+
+        /// <summary>
+        /// list of sort keys specific to this collection
+        /// </summary>
+        internal List<InternalTrees.SortKey> SortKeys
+        {
+            get { return m_sortKeys; }
+        }
+
+        /// <summary>
+        /// Discriminator Value for this collection (for a given NestOp).
+        /// Should we break this out into a subtype of CollectionInfo
+        /// </summary>
+        internal object DiscriminatorValue
+        {
+            get { return m_discriminatorValue; }
+        }
+
+        #endregion
+
+        #region constructors
+        internal CollectionInfo(Var collectionVar, ColumnMap columnMap, VarList flattenedElementVars, VarVec keys, List<InternalTrees.SortKey> sortKeys, object discriminatorValue)
+        {
+            m_collectionVar = collectionVar;
+            m_columnMap = columnMap;
+            m_flattenedElementVars = flattenedElementVars;
+            m_keys = keys;
+            m_sortKeys = sortKeys;
+            m_discriminatorValue = discriminatorValue;
+        }
+        #endregion
+
+        #region private state
+        private Var m_collectionVar;    // the collection Var
+        private ColumnMap m_columnMap;  // column map for the collection element
+        private VarList m_flattenedElementVars; // elementVars, removing collections;
+        private VarVec m_keys;              //list of keys specific to this collection
+        private List<InternalTrees.SortKey> m_sortKeys;          //list of sort keys specific to this collection
+        private object m_discriminatorValue;
+        #endregion
+    }
+
+    /// <summary>
+    /// Base class for Nest operations
+    /// </summary>
+    internal abstract class NestBaseOp : PhysicalOp
+    {
+        #region publics
+
+        /// <summary>
+        /// (Ordered) list of prefix sort keys (defines ordering of results)
+        /// </summary>
+        internal List<SortKey> PrefixSortKeys
+        {
+            get { return m_prefixSortKeys; }
+        }
+
+        /// <summary>
+        /// Outputs of the NestOp. Includes the Keys obviously, and one Var for each of
+        /// the collections produced. In addition, this may also include non-key vars
+        /// from the outer row
+        /// </summary>
+        internal VarVec Outputs 
+        { 
+            get { return m_outputs; } 
+        }
+        
+        /// <summary>
+        /// Information about each collection managed by the NestOp
+        /// </summary>
+        internal List<CollectionInfo> CollectionInfo
+        {
+            get { return m_collectionInfoList; }
+        }
+        #endregion
+
+        #region constructors
+        internal NestBaseOp(OpType opType, List<SortKey> prefixSortKeys, 
+            VarVec outputVars, 
+            List<CollectionInfo> collectionInfoList)
+            : base(opType)
+        {
+            m_outputs = outputVars;
+            m_collectionInfoList = collectionInfoList;
+            m_prefixSortKeys = prefixSortKeys;
+        }
+        #endregion
+
+        #region private state
+        private List<SortKey> m_prefixSortKeys; // list of sort key prefixes
+        private VarVec m_outputs; // list of all output vars
+        private List<CollectionInfo> m_collectionInfoList;
+        #endregion
+    }
+
+    /// <summary>
+    /// Single-stream nest aggregation Op. 
+    /// (Somewhat similar to a group-by op - should we merge these?)
+    /// </summary>
+    internal class SingleStreamNestOp : NestBaseOp
+    {
+        #region publics
+        /// <summary>
+        /// 1 child - the input
+        /// </summary>
+        internal override int Arity { get { return 1; } }
+
+        /// <summary>
+        /// The discriminator Var (when there are multiple collections)
+        /// </summary>
+        internal Var Discriminator 
+        { 
+            get { return m_discriminator; } 
+        }
+        /// <summary>
+        /// List of postfix sort keys (mostly to deal with multi-level nested collections)
+        /// </summary>
+        internal List<SortKey> PostfixSortKeys
+        {
+            get { return m_postfixSortKeys; }
+        }
+        /// <summary>
+        /// Set of keys for this nest operation
+        /// </summary>
+        internal VarVec Keys
+        {
+            get { return m_keys; }
+        }
+
+        /// <summary>
+        /// Visitor pattern method
+        /// </summary>
+        /// <param name="v">The BasicOpVisitor that is visiting this Op</param>
+        /// <param name="n">The Node that references this Op</param>
+        [DebuggerNonUserCode]
+        internal override void Accept(BasicOpVisitor v, Node n) 
+        { 
+            v.Visit(this, n); 
+        }
+
+        /// <summary>
+        /// Visitor pattern method for visitors with a return value
+        /// </summary>
+        /// <param name="v">The visitor</param>
+        /// <param name="n">The node in question</param>
+        /// <returns>An instance of TResultType</returns>
+        [DebuggerNonUserCode]
+        internal override TResultType Accept<TResultType>(BasicOpVisitorOfT<TResultType> v, Node n) 
+        { 
+            return v.Visit(this, n); 
+        }
+
+        #endregion
+
+        #region constructors
+        internal SingleStreamNestOp(VarVec keys,
+            List<SortKey> prefixSortKeys, List<SortKey> postfixSortKeys, 
+            VarVec outputVars, List<CollectionInfo> collectionInfoList, 
+            Var discriminatorVar)
+            : base(OpType.SingleStreamNest, prefixSortKeys, outputVars, collectionInfoList)
+        {
+            m_keys = keys;
+            m_postfixSortKeys = postfixSortKeys;
+            m_discriminator = discriminatorVar;
+        }
+        #endregion
+
+        #region private state
+        private VarVec m_keys; // keys for this operation
+        private Var m_discriminator; // Var describing the discriminator
+        List<SortKey> m_postfixSortKeys; // list of postfix sort keys 
+        #endregion
+    }
+
+    /// <summary>
+    /// Represents a multi-stream nest operation. The first input represents the 
+    /// container row, while all the other inputs represent collections
+    /// </summary>
+    internal class MultiStreamNestOp : NestBaseOp
+    {
+        #region publics
+        /// <summary>
+        /// Visitor pattern method
+        /// </summary>
+        /// <param name="v">The BasicOpVisitor that is visiting this Op</param>
+        /// <param name="n">The Node that references this Op</param>
+        [DebuggerNonUserCode]
+        internal override void Accept(BasicOpVisitor v, Node n) { v.Visit(this, n); }
+
+        /// <summary>
+        /// Visitor pattern method for visitors with a return value
+        /// </summary>
+        /// <param name="v">The visitor</param>
+        /// <param name="n">The node in question</param>
+        /// <returns>An instance of TResultType</returns>
+        [DebuggerNonUserCode]
+        internal override TResultType Accept<TResultType>(BasicOpVisitorOfT<TResultType> v, Node n) { return v.Visit(this, n); }
+        #endregion
+
+        #region constructors
+        internal MultiStreamNestOp(List<SortKey> prefixSortKeys, VarVec outputVars, 
+            List<CollectionInfo> collectionInfoList)
+            : base(OpType.MultiStreamNest, prefixSortKeys, outputVars, collectionInfoList)
+        {
+        }
+        #endregion
+
+        #region private state
+        #endregion
+    }
+}

mcs/class/referencesource/System.Data.Entity/System/Data/Query/InternalTrees/RelPropertyHelper.cs

@@ -0,0 +1,232 @@
+//---------------------------------------------------------------------
+// <copyright file="RelPropertyHelper.cs" company="Microsoft">
+//      Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//
+// @owner  [....]
+// @backupOwner [....]
+//---------------------------------------------------------------------
+
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.Diagnostics;
+using System.Data.Common;
+using System.Data.Metadata.Edm;
+
+namespace System.Data.Query.InternalTrees
+{
+
+    /// <summary>
+    /// A "Rel" property is best thought of as a collocated reference (aka foreign key). 
+    /// Any entity may have zero or more rel-properties carried along with it (purely
+    /// as a means to optimize for common relationship traversal scenarios)
+    /// 
+    /// Although the definition is lax here, we only deal with RelProperties that
+    /// are one-ended (ie) the target multiplicity is at most One.
+    /// 
+    /// Consider for example, an Order entity with a (N:1) Order-Customer relationship. The Customer ref
+    /// will be treated as a rel property for the Order entity. 
+    /// Similarly, the OrderLine entity may have an Order ref rel property (assuming that there was 
+    /// a N:1 relationship between OrderLine and Order)
+    /// </summary>
+    internal sealed class RelProperty
+    {
+        #region private state
+        private readonly RelationshipType m_relationshipType;
+        private readonly RelationshipEndMember m_fromEnd;
+        private readonly RelationshipEndMember m_toEnd;
+        #endregion
+
+        #region constructors
+        internal RelProperty(RelationshipType relationshipType, RelationshipEndMember fromEnd, RelationshipEndMember toEnd)
+        {
+            m_relationshipType = relationshipType;
+            m_fromEnd = fromEnd;
+            m_toEnd = toEnd;
+        }
+        #endregion
+
+        #region public APIs
+        /// <summary>
+        /// The relationship
+        /// </summary>
+        public RelationshipType Relationship { get { return m_relationshipType; } }
+
+        /// <summary>
+        /// The source end of the relationship
+        /// </summary>
+        public RelationshipEndMember FromEnd { get { return m_fromEnd; } }
+
+        /// <summary>
+        /// the target end of the relationship
+        /// </summary>
+        public RelationshipEndMember ToEnd { get { return m_toEnd; } }
+
+        /// <summary>
+        /// Our definition of equality
+        /// </summary>
+        /// <param name="obj"></param>
+        /// <returns></returns>
+        public override bool Equals(object obj)
+        {
+            RelProperty other = obj as RelProperty;
+            return (other != null &&
+                this.Relationship.EdmEquals(other.Relationship) &&
+                this.FromEnd.EdmEquals(other.FromEnd) &&
+                this.ToEnd.EdmEquals(other.ToEnd));
+        }
+
+        /// <summary>
+        /// our hash code
+        /// </summary>
+        /// <returns></returns>
+        public override int GetHashCode()
+        {
+            return this.ToEnd.Identity.GetHashCode();
+        }
+
+        /// <summary>
+        /// String form
+        /// </summary>
+        /// <returns></returns>
+        [DebuggerNonUserCode]
+        public override string ToString()
+        {
+            return m_relationshipType.ToString() + ":" +
+                m_fromEnd.ToString() + ":" +
+                m_toEnd.ToString();
+        }
+
+        #endregion
+    }
+
+    /// <summary>
+    /// A helper class for all rel-properties
+    /// </summary>
+    internal sealed class RelPropertyHelper
+    {
+        #region private state
+        private Dictionary<EntityTypeBase, List<RelProperty>> _relPropertyMap;
+        private HashSet<RelProperty> _interestingRelProperties;
+        #endregion
+
+        #region private methods
+        /// <summary>
+        /// Add the rel property induced by the specified relationship, (if the target
+        /// end has a multiplicity of one)
+        /// We only keep track of rel-properties that are "interesting" 
+        /// </summary>
+        /// <param name="associationType">the association relationship</param>
+        /// <param name="fromEnd">source end of the relationship traversal</param>
+        /// <param name="toEnd">target end of the traversal</param>
+        private void AddRelProperty(AssociationType associationType,
+            AssociationEndMember fromEnd, AssociationEndMember toEnd)
+        {
+            if (toEnd.RelationshipMultiplicity == RelationshipMultiplicity.Many)
+            {
+                return;
+            }
+            RelProperty prop = new RelProperty(associationType, fromEnd, toEnd);
+            if (_interestingRelProperties == null ||
+                !_interestingRelProperties.Contains(prop))
+            {
+                return;
+            }
+
+            EntityTypeBase entityType = (EntityTypeBase)((RefType)fromEnd.TypeUsage.EdmType).ElementType;
+            List<RelProperty> propList;
+            if (!_relPropertyMap.TryGetValue(entityType, out propList))
+            {
+                propList = new List<RelProperty>();
+                _relPropertyMap[entityType] = propList;
+            }
+            propList.Add(prop);
+        }
+
+        /// <summary>
+        /// Add any rel properties that are induced by the supplied relationship
+        /// </summary>
+        /// <param name="relationshipType">the relationship</param>
+        private void ProcessRelationship(RelationshipType relationshipType)
+        {
+            AssociationType associationType = relationshipType as AssociationType;
+            if (associationType == null)
+            {
+                return;
+            }
+
+            // Handle only binary associations
+            if (associationType.AssociationEndMembers.Count != 2)
+            {
+                return;
+            }
+
+            AssociationEndMember end0 = associationType.AssociationEndMembers[0];
+            AssociationEndMember end1 = associationType.AssociationEndMembers[1];
+
+            AddRelProperty(associationType, end0, end1);
+            AddRelProperty(associationType, end1, end0);
+        }
+
+        #endregion
+
+        #region constructors
+        internal RelPropertyHelper(MetadataWorkspace ws, HashSet<RelProperty> interestingRelProperties)
+        {
+            _relPropertyMap = new Dictionary<EntityTypeBase, List<RelProperty>>();
+            _interestingRelProperties = interestingRelProperties;
+
+            foreach (RelationshipType relationshipType in ws.GetItems<RelationshipType>(DataSpace.CSpace))
+            {
+                ProcessRelationship(relationshipType);
+            }
+        }
+        #endregion
+
+        #region public APIs
+
+        /// <summary>
+        /// Get the rel properties declared by this type (and *not* by any of its subtypes)
+        /// </summary>
+        /// <param name="entityType">the entity type</param>
+        /// <returns>set of rel properties declared for this type</returns>
+        internal IEnumerable<RelProperty> GetDeclaredOnlyRelProperties(EntityTypeBase entityType)
+        {
+            List<RelProperty> relProperties;
+            if (_relPropertyMap.TryGetValue(entityType, out relProperties))
+            {
+                foreach (RelProperty p in relProperties)
+                {
+                    yield return p;
+                }
+            }
+            yield break;
+        }
+
+        /// <summary>
+        /// Get the rel-properties of this entity and its supertypes (starting from the root)
+        /// </summary>
+        /// <param name="entityType">the entity type</param>
+        /// <returns>set of rel-properties for this entity type (and its supertypes)</returns>
+        internal IEnumerable<RelProperty> GetRelProperties(EntityTypeBase entityType)
+        {
+            if (entityType.BaseType != null)
+            {
+                foreach (RelProperty p in GetRelProperties(entityType.BaseType as EntityTypeBase))
+                {
+                    yield return p;
+                }
+            }
+
+            foreach (RelProperty p in GetDeclaredOnlyRelProperties(entityType))
+            {
+                yield return p;
+            }
+
+        }
+
+        #endregion
+    }
+
+}

mcs/class/referencesource/System.Data.Entity/System/Data/Query/InternalTrees/Rule.cs

@@ -0,0 +1,183 @@
+//---------------------------------------------------------------------
+// <copyright file="Rule.cs" company="Microsoft">
+//      Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//
+// @owner  [....]
+// @backupOwner [....]
+//---------------------------------------------------------------------
+
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Globalization;
+
+namespace System.Data.Query.InternalTrees
+{
+    /// <summary>
+    /// A Rule - more specifically, a transformation rule - describes an action that is to
+    /// be taken when a specific kind of subtree is found in the tree
+    /// </summary>
+    internal abstract class Rule
+    {
+        /// <summary>
+        /// The "callback" function for each rule. 
+        /// Every callback function must return true if the subtree has
+        /// been modified (or a new subtree has been returned); and must return false
+        /// otherwise. If the root of the subtree has not changed, but some internal details
+        /// of the subtree have changed, it is the responsibility of the rule to update any
+        /// local bookkeeping information.
+        /// </summary>
+        /// <param name="context">The rule processing context</param>
+        /// <param name="subTree">the subtree to operate on</param>
+        /// <param name="newSubTree">possibly transformed subtree</param>
+        /// <returns>transformation status - true, if there was some change; false otherwise</returns>
+        internal delegate bool ProcessNodeDelegate(RuleProcessingContext context, Node subTree, out Node newSubTree);
+
+        #region private state
+        private ProcessNodeDelegate m_nodeDelegate;
+        private OpType m_opType;
+        #endregion
+
+        #region Constructors
+        /// <summary>
+        /// Basic constructor
+        /// </summary>
+        /// <param name="opType">The OpType we're interested in processing</param>
+        /// <param name="nodeProcessDelegate">The callback to invoke</param>
+        protected Rule(OpType opType, ProcessNodeDelegate nodeProcessDelegate)
+        {
+            Debug.Assert(nodeProcessDelegate != null, "null process delegate");
+            Debug.Assert(opType != OpType.NotValid, "bad OpType");
+            Debug.Assert(opType != OpType.Leaf, "bad OpType - Leaf");
+
+            m_opType = opType;
+            m_nodeDelegate = nodeProcessDelegate;
+        }
+        #endregion
+
+        #region protected methods
+
+        #endregion
+
+        #region public methods
+        /// <summary>
+        /// Does the rule match the current node?
+        /// </summary>
+        /// <param name="node">the node in question</param>
+        /// <returns>true, if a match was found</returns>
+        internal abstract bool Match(Node node);
+
+        /// <summary>
+        /// We need to invoke the specified callback on the subtree in question - but only
+        /// if the match succeeds
+        /// </summary>
+        /// <param name="ruleProcessingContext">Current rule processing context</param>
+        /// <param name="node">The node (subtree) to process</param>
+        /// <param name="newNode">the (possibly) modified subtree</param>
+        /// <returns>true, if the subtree was modified</returns>
+        internal bool Apply(RuleProcessingContext ruleProcessingContext, Node node, out Node newNode)
+        {
+            // invoke the real callback
+            return m_nodeDelegate(ruleProcessingContext, node, out newNode);
+        }
+
+        /// <summary>
+        /// The OpType we're interested in transforming
+        /// </summary>
+        internal OpType RuleOpType
+        {
+            get { return m_opType; }
+        }
+
+#if DEBUG
+        /// <summary>
+        /// The method name for the rule
+        /// </summary>
+        internal string MethodName
+        {
+            get { return m_nodeDelegate.Method.Name; }
+        }
+#endif
+
+        #endregion
+    }
+
+    /// <summary>
+    /// A SimpleRule is a rule that specifies a specific OpType to look for, and an
+    /// appropriate action to take when such an Op is identified
+    /// </summary>
+    internal sealed class SimpleRule : Rule
+    {
+        #region private state
+        #endregion
+
+        #region constructors
+        /// <summary>
+        /// Basic constructor.
+        /// </summary>
+        /// <param name="opType">The OpType we're interested in</param>
+        /// <param name="processDelegate">The callback to invoke when we see such an Op</param>
+        internal SimpleRule(OpType opType, ProcessNodeDelegate processDelegate)
+            : base(opType, processDelegate)
+        {
+        }
+        #endregion
+
+        #region overriden methods
+        internal override bool Match(Node node)
+        {
+            return node.Op.OpType == this.RuleOpType;
+        }
+        #endregion
+    }
+
+    /// <summary>
+    /// A PatternMatchRule allows for a pattern to be specified to identify interesting
+    /// subtrees, rather than just an OpType
+    /// </summary>
+    internal sealed class PatternMatchRule: Rule
+    {
+        #region private state
+        private Node m_pattern;
+        #endregion
+
+        #region constructors
+        /// <summary>
+        /// Basic constructor
+        /// </summary>
+        /// <param name="pattern">The pattern to look for</param>
+        /// <param name="processDelegate">The callback to invoke when such a pattern is identified</param>
+        internal PatternMatchRule(Node pattern, ProcessNodeDelegate processDelegate)
+            : base(pattern.Op.OpType, processDelegate)
+        {
+            Debug.Assert(pattern != null, "null pattern");
+            Debug.Assert(pattern.Op != null, "null pattern Op");
+            m_pattern = pattern;
+        }
+        #endregion
+
+        #region private methods
+        private bool Match(Node pattern, Node original)
+        {
+            if (pattern.Op.OpType == OpType.Leaf)
+                return true;
+            if (pattern.Op.OpType != original.Op.OpType)
+                return false;
+            if (pattern.Children.Count != original.Children.Count)
+                return false;
+            for (int i = 0; i < pattern.Children.Count; i++)
+                if (!Match(pattern.Children[i], original.Children[i]))
+                    return false;
+            return true;
+        }
+        #endregion
+
+        #region overridden methods
+        internal override bool Match(Node node)
+        {
+            return Match(m_pattern, node);
+        }
+        #endregion
+    }
+}

mcs/class/referencesource/System.Data.Entity/System/Data/Query/InternalTrees/RulePatternOps.cs

@@ -0,0 +1,40 @@
+//---------------------------------------------------------------------
+// <copyright file="RulePatternOps.cs" company="Microsoft">
+//      Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//
+// @owner  [....]
+// @backupOwner [....]
+//---------------------------------------------------------------------
+
+using System;
+using System.Collections.Generic;
+using System.Data.Metadata.Edm;
+using System.Globalization;
+
+namespace System.Data.Query.InternalTrees
+{
+    /// <summary>
+    /// LeafOp - matches any subtree 
+    /// </summary>
+    internal sealed class LeafOp : RulePatternOp
+    {
+        /// <summary>
+        /// The singleton instance of this class
+        /// </summary>
+        internal static readonly LeafOp Instance = new LeafOp();
+        internal static readonly LeafOp Pattern = Instance;
+
+        /// <summary>
+        /// 0 children
+        /// </summary>
+        internal override int Arity { get { return 0; } }
+
+        #region constructors
+        /// <summary>
+        /// Niladic constructor
+        /// </summary>
+        private LeafOp() : base(OpType.Leaf) { }
+        #endregion
+    }
+}