Code:
/ 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / fx / src / DLinq / Dlinq / SqlClient / Query / SqlExpander.cs / 1305376 / SqlExpander.cs
using System; using System.Collections.Generic; using System.Linq.Expressions; using System.Reflection; using System.Data.Linq; using System.Data.Linq.Mapping; using System.Data.Linq.Provider; using System.Linq; using System.Data.Linq.SqlClient; using System.Diagnostics.CodeAnalysis; namespace System.Data.Linq.SqlClient { // duplicates an expression up until a column or column ref is encountered // goes 'deep' through alias ref's // assumes that columnizing has been done already internal class SqlExpander { SqlFactory factory; internal SqlExpander(SqlFactory factory) { this.factory = factory; } internal SqlExpression Expand(SqlExpression exp) { return (new Visitor(this.factory)).VisitExpression(exp); } class Visitor : SqlDuplicator.DuplicatingVisitor { SqlFactory factory; Expression sourceExpression; internal Visitor(SqlFactory factory) : base(true) { this.factory = factory; } internal override SqlExpression VisitColumnRef(SqlColumnRef cref) { return cref; } internal override SqlExpression VisitColumn(SqlColumn col) { return new SqlColumnRef(col); } internal override SqlExpression VisitSharedExpression(SqlSharedExpression shared) { return this.VisitExpression(shared.Expression); } internal override SqlExpression VisitSharedExpressionRef(SqlSharedExpressionRef sref) { return this.VisitExpression(sref.SharedExpression.Expression); } internal override SqlExpression VisitAliasRef(SqlAliasRef aref) { SqlNode node = aref.Alias.Node; if (node is SqlTable || node is SqlTableValuedFunctionCall) { return aref; } SqlUnion union = node as SqlUnion; if (union != null) { return this.ExpandUnion(union); } SqlSelect ss = node as SqlSelect; if (ss != null) { return this.VisitExpression(ss.Selection); } SqlExpression exp = node as SqlExpression; if (exp != null) return this.VisitExpression(exp); throw Error.CouldNotHandleAliasRef(node.NodeType); } internal override SqlExpression VisitSubSelect(SqlSubSelect ss) { return (SqlExpression)new SqlDuplicator().Duplicate(ss); } internal override SqlNode VisitLink(SqlLink link) { SqlExpression expansion = this.VisitExpression(link.Expansion); SqlExpression[] exprs = new SqlExpression[link.KeyExpressions.Count]; for (int i = 0, n = exprs.Length; i < n; i++) { exprs[i] = this.VisitExpression(link.KeyExpressions[i]); } return new SqlLink(link.Id, link.RowType, link.ClrType, link.SqlType, link.Expression, link.Member, exprs, expansion, link.SourceExpression); } private SqlExpression ExpandUnion(SqlUnion union) { Listexprs = new List (2); this.GatherUnionExpressions(union, exprs); this.sourceExpression = union.SourceExpression; SqlExpression result = this.ExpandTogether(exprs); return result; } private void GatherUnionExpressions(SqlNode node, List exprs) { SqlUnion union = node as SqlUnion; if (union != null) { this.GatherUnionExpressions(union.Left, exprs); this.GatherUnionExpressions(union.Right, exprs); } else { SqlSelect sel = node as SqlSelect; if (sel != null) { SqlAliasRef aref = sel.Selection as SqlAliasRef; if (aref != null) { this.GatherUnionExpressions(aref.Alias.Node, exprs); } else { exprs.Add(sel.Selection); } } } } [SuppressMessage("Microsoft.Performance", "CA1809:AvoidExcessiveLocals", Justification="These issues are related to our use of if-then and case statements for node types, which adds to the complexity count however when reviewed they are easy to navigate and understand.")] [SuppressMessage("Microsoft.Maintainability", "CA1505:AvoidUnmaintainableCode", Justification = "These issues are related to our use of if-then and case statements for node types, which adds to the complexity count however when reviewed they are easy to navigate and understand.")] [SuppressMessage("Microsoft.Maintainability", "CA1502:AvoidExcessiveComplexity", Justification = "These issues are related to our use of if-then and case statements for node types, which adds to the complexity count however when reviewed they are easy to navigate and understand.")] private SqlExpression ExpandTogether(List exprs) { switch (exprs[0].NodeType) { case SqlNodeType.MethodCall: { SqlMethodCall[] mcs = new SqlMethodCall[exprs.Count]; for (int i = 0; i < mcs.Length; ++i) { mcs[i] = (SqlMethodCall)exprs[i]; } List expandedArgs = new List (); for (int i = 0; i < mcs[0].Arguments.Count; ++i) { List args = new List (); for (int j = 0; j < mcs.Length; ++j) { args.Add(mcs[j].Arguments[i]); } SqlExpression expanded = this.ExpandTogether(args); expandedArgs.Add(expanded); } return factory.MethodCall(mcs[0].Method, mcs[0].Object, expandedArgs.ToArray(), mcs[0].SourceExpression); } case SqlNodeType.ClientCase: { // Are they all the same? SqlClientCase[] scs = new SqlClientCase[exprs.Count]; scs[0] = (SqlClientCase)exprs[0]; for (int i = 1; i < scs.Length; ++i) { scs[i] = (SqlClientCase)exprs[i]; } // Expand expressions together. List expressions = new List (); for (int i = 0; i < scs.Length; ++i) { expressions.Add(scs[i].Expression); } SqlExpression expression = this.ExpandTogether(expressions); // Expand individual expressions together. List whens = new List (); for (int i = 0; i < scs[0].Whens.Count; ++i) { List scos = new List (); for (int j = 0; j < scs.Length; ++j) { SqlClientWhen when = scs[j].Whens[i]; scos.Add(when.Value); } whens.Add(new SqlClientWhen(scs[0].Whens[i].Match, this.ExpandTogether(scos))); } return new SqlClientCase(scs[0].ClrType, expression, whens, scs[0].SourceExpression); } case SqlNodeType.TypeCase: { // Are they all the same? SqlTypeCase[] tcs = new SqlTypeCase[exprs.Count]; tcs[0] = (SqlTypeCase)exprs[0]; for (int i = 1; i < tcs.Length; ++i) { tcs[i] = (SqlTypeCase)exprs[i]; } // Expand discriminators together. List discriminators = new List (); for (int i = 0; i < tcs.Length; ++i) { discriminators.Add(tcs[i].Discriminator); } SqlExpression discriminator = this.ExpandTogether(discriminators); // Write expanded discriminators back in. for (int i = 0; i < tcs.Length; ++i) { tcs[i].Discriminator = discriminators[i]; } // Expand individual type bindings together. List whens = new List (); for (int i = 0; i < tcs[0].Whens.Count; ++i) { List scos = new List (); for (int j = 0; j < tcs.Length; ++j) { SqlTypeCaseWhen when = tcs[j].Whens[i]; scos.Add(when.TypeBinding); } SqlExpression expanded = this.ExpandTogether(scos); whens.Add(new SqlTypeCaseWhen(tcs[0].Whens[i].Match, expanded)); } return factory.TypeCase(tcs[0].ClrType, tcs[0].RowType, discriminator, whens, tcs[0].SourceExpression); } case SqlNodeType.New: { // first verify all are similar client objects... SqlNew[] cobs = new SqlNew[exprs.Count]; cobs[0] = (SqlNew)exprs[0]; for (int i = 1, n = exprs.Count; i < n; i++) { if (exprs[i] == null || exprs[i].NodeType != SqlNodeType.New) throw Error.UnionIncompatibleConstruction(); cobs[i] = (SqlNew)exprs[1]; if (cobs[i].Members.Count != cobs[0].Members.Count) throw Error.UnionDifferentMembers(); for (int m = 0, mn = cobs[0].Members.Count; m < mn; m++) { if (cobs[i].Members[m].Member != cobs[0].Members[m].Member) { throw Error.UnionDifferentMemberOrder(); } } } SqlMemberAssign[] bindings = new SqlMemberAssign[cobs[0].Members.Count]; for (int m = 0, mn = bindings.Length; m < mn; m++) { List mexprs = new List (); for (int i = 0, n = exprs.Count; i < n; i++) { mexprs.Add(cobs[i].Members[m].Expression); } bindings[m] = new SqlMemberAssign(cobs[0].Members[m].Member, this.ExpandTogether(mexprs)); for (int i = 0, n = exprs.Count; i < n; i++) { cobs[i].Members[m].Expression = mexprs[i]; } } SqlExpression[] arguments = new SqlExpression[cobs[0].Args.Count]; for (int m = 0, mn = arguments.Length; m < mn; ++m) { List mexprs = new List (); for (int i = 0, n = exprs.Count; i < n; i++) { mexprs.Add(cobs[i].Args[m]); } arguments[m] = ExpandTogether(mexprs); } return factory.New(cobs[0].MetaType, cobs[0].Constructor, arguments, cobs[0].ArgMembers, bindings, exprs[0].SourceExpression); } case SqlNodeType.Link: { SqlLink[] links = new SqlLink[exprs.Count]; links[0] = (SqlLink)exprs[0]; for (int i = 1, n = exprs.Count; i < n; i++) { if (exprs[i] == null || exprs[i].NodeType != SqlNodeType.Link) throw Error.UnionIncompatibleConstruction(); links[i] = (SqlLink)exprs[i]; if (links[i].KeyExpressions.Count != links[0].KeyExpressions.Count || links[i].Member != links[0].Member || (links[i].Expansion != null) != (links[0].Expansion != null)) throw Error.UnionIncompatibleConstruction(); } SqlExpression[] kexprs = new SqlExpression[links[0].KeyExpressions.Count]; List lexprs = new List (); for (int k = 0, nk = links[0].KeyExpressions.Count; k < nk; k++) { lexprs.Clear(); for (int i = 0, n = exprs.Count; i < n; i++) { lexprs.Add(links[i].KeyExpressions[k]); } kexprs[k] = this.ExpandTogether(lexprs); for (int i = 0, n = exprs.Count; i < n; i++) { links[i].KeyExpressions[k] = lexprs[i]; } } SqlExpression expansion = null; if (links[0].Expansion != null) { lexprs.Clear(); for (int i = 0, n = exprs.Count; i < n; i++) { lexprs.Add(links[i].Expansion); } expansion = this.ExpandTogether(lexprs); for (int i = 0, n = exprs.Count; i < n; i++) { links[i].Expansion = lexprs[i]; } } return new SqlLink(links[0].Id, links[0].RowType, links[0].ClrType, links[0].SqlType, links[0].Expression, links[0].Member, kexprs, expansion, links[0].SourceExpression); } case SqlNodeType.Value: { /* * ExprSet of all literals of the same value reduce to just a single literal. */ SqlValue val0 = (SqlValue)exprs[0]; for (int i = 1; i < exprs.Count; ++i) { SqlValue val = (SqlValue)exprs[i]; if (!object.Equals(val.Value, val0.Value)) return this.ExpandIntoExprSet(exprs); } return val0; } case SqlNodeType.OptionalValue: { if (exprs[0].SqlType.CanBeColumn) { goto default; } List hvals = new List (exprs.Count); List vals = new List (exprs.Count); for (int i = 0, n = exprs.Count; i < n; i++) { if (exprs[i] == null || exprs[i].NodeType != SqlNodeType.OptionalValue) { throw Error.UnionIncompatibleConstruction(); } SqlOptionalValue sov = (SqlOptionalValue)exprs[i]; hvals.Add(sov.HasValue); vals.Add(sov.Value); } return new SqlOptionalValue(this.ExpandTogether(hvals), this.ExpandTogether(vals)); } case SqlNodeType.OuterJoinedValue: { if (exprs[0].SqlType.CanBeColumn) { goto default; } List values = new List (exprs.Count); for (int i = 0, n = exprs.Count; i < n; i++) { if (exprs[i] == null || exprs[i].NodeType != SqlNodeType.OuterJoinedValue) { throw Error.UnionIncompatibleConstruction(); } SqlUnary su = (SqlUnary)exprs[i]; values.Add(su.Operand); } return factory.Unary(SqlNodeType.OuterJoinedValue, this.ExpandTogether(values)); } case SqlNodeType.DiscriminatedType: { SqlDiscriminatedType sdt0 = (SqlDiscriminatedType)exprs[0]; List foos = new List (exprs.Count); foos.Add(sdt0.Discriminator); for (int i = 1, n = exprs.Count; i < n; i++) { SqlDiscriminatedType sdtN = (SqlDiscriminatedType)exprs[i]; if (sdtN.TargetType != sdt0.TargetType) { throw Error.UnionIncompatibleConstruction(); } foos.Add(sdtN.Discriminator); } return factory.DiscriminatedType(this.ExpandTogether(foos), ((SqlDiscriminatedType)exprs[0]).TargetType); } case SqlNodeType.ClientQuery: case SqlNodeType.Multiset: case SqlNodeType.Element: case SqlNodeType.Grouping: throw Error.UnionWithHierarchy(); default: return this.ExpandIntoExprSet(exprs); } } /// /// Expand a set of expressions into a single expr set. /// This is typically a fallback when there is no other way to unify a set of expressions. /// private SqlExpression ExpandIntoExprSet(Listexprs) { SqlExpression[] rexprs = new SqlExpression[exprs.Count]; for (int i = 0, n = exprs.Count; i < n; i++) { rexprs[i] = this.VisitExpression(exprs[i]); } return this.factory.ExprSet(rexprs, this.sourceExpression); } } } } // File provided for Reference Use Only by Microsoft Corporation (c) 2007. // Copyright (c) Microsoft Corporation. All rights reserved.
Link Menu

This book is available now!
Buy at Amazon US or
Buy at Amazon UK
- KeyFrames.cs
- MulticastDelegate.cs
- Stream.cs
- WebBrowserPermission.cs
- XPathDocument.cs
- FontUnit.cs
- EventSetter.cs
- DataBoundLiteralControl.cs
- DataContract.cs
- AnonymousIdentificationSection.cs
- ScriptReferenceEventArgs.cs
- DescriptionAttribute.cs
- Interop.cs
- DocumentSchemaValidator.cs
- AttributeEmitter.cs
- JsonServiceDocumentSerializer.cs
- ModelPerspective.cs
- PreloadedPackages.cs
- Visual.cs
- GuidTagList.cs
- DebuggerAttributes.cs
- Compiler.cs
- RegionInfo.cs
- peersecuritysettings.cs
- InputReferenceExpression.cs
- OutputCacheSettingsSection.cs
- NavigationFailedEventArgs.cs
- RadioButton.cs
- SvcMapFileLoader.cs
- CollectionConverter.cs
- MiniLockedBorderGlyph.cs
- EntityContainerEmitter.cs
- TimeSpan.cs
- MergablePropertyAttribute.cs
- Win32MouseDevice.cs
- ChildChangedEventArgs.cs
- DataIdProcessor.cs
- EllipseGeometry.cs
- PropertyFilterAttribute.cs
- _NetworkingPerfCounters.cs
- ToolStripRenderEventArgs.cs
- SingletonInstanceContextProvider.cs
- ManipulationDelta.cs
- ToolStripDropDownButton.cs
- StaticContext.cs
- MiniAssembly.cs
- Atom10FormatterFactory.cs
- DateTimeUtil.cs
- RootNamespaceAttribute.cs
- ChannelCredentials.cs
- SecurityUtils.cs
- WebServiceEnumData.cs
- HttpCapabilitiesBase.cs
- UIElementHelper.cs
- TextSelectionHighlightLayer.cs
- AcceleratedTokenAuthenticator.cs
- WizardSideBarListControlItem.cs
- PixelFormat.cs
- DiagnosticSection.cs
- RoleManagerSection.cs
- Int32Collection.cs
- IndexOutOfRangeException.cs
- SafeMILHandleMemoryPressure.cs
- Expression.cs
- BinaryMethodMessage.cs
- EditorZoneDesigner.cs
- ArrangedElementCollection.cs
- Emitter.cs
- EntitySetBase.cs
- CompilerTypeWithParams.cs
- TabControl.cs
- MD5.cs
- MonthChangedEventArgs.cs
- SharedUtils.cs
- CompilerGlobalScopeAttribute.cs
- SkewTransform.cs
- SecureStringHasher.cs
- WindowsBrush.cs
- RegistryKey.cs
- InProcStateClientManager.cs
- ListViewItem.cs
- CreateUserErrorEventArgs.cs
- WebPartEditorCancelVerb.cs
- GridViewAutomationPeer.cs
- Content.cs
- CompiledQuery.cs
- FunctionImportElement.cs
- UnsafeNativeMethods.cs
- CorrelationManager.cs
- RefExpr.cs
- ArraySubsetEnumerator.cs
- SoapObjectReader.cs
- WhitespaceSignificantCollectionAttribute.cs
- ALinqExpressionVisitor.cs
- SoapTypeAttribute.cs
- InvokeSchedule.cs
- MaterialGroup.cs
- PlatformCulture.cs
- PartialCachingAttribute.cs
- ReadContentAsBinaryHelper.cs