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1617 lines
76 KiB
C#
1617 lines
76 KiB
C#
//---------------------------------------------------------------------
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// <copyright file="ExpressionConverter.cs" company="Microsoft">
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// Copyright (c) Microsoft Corporation. All rights reserved.
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// </copyright>
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//
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// @owner Microsoft
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//---------------------------------------------------------------------
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namespace System.Data.Objects.ELinq
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{
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using System.Collections;
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using System.Collections.Generic;
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using System.Data.Common;
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using System.Data.Common.CommandTrees;
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using System.Data.Common.CommandTrees.ExpressionBuilder;
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using System.Data.Common.EntitySql;
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using System.Data.Common.Utils;
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using System.Data.Entity;
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using System.Data.Metadata.Edm;
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using System.Diagnostics;
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using System.Globalization;
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using System.Linq;
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using System.Linq.Expressions;
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using System.Reflection;
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using System.Text;
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/// <summary>
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/// Class supporting conversion of LINQ expressions to EDM CQT expressions.
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/// </summary>
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internal sealed partial class ExpressionConverter
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{
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#region Fields
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private readonly Funcletizer _funcletizer;
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private readonly Perspective _perspective;
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private readonly Expression _expression;
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private readonly BindingContext _bindingContext;
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private Func<bool> _recompileRequired;
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private List<KeyValuePair<ObjectParameter, QueryParameterExpression>> _parameters;
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private Dictionary<DbExpression, Span> _spanMappings;
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private MergeOption? _mergeOption;
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private Dictionary<Type, InitializerMetadata> _initializers;
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private Span _span;
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private HashSet<ObjectQuery> _inlineEntitySqlQueries;
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private int _ignoreInclude;
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private readonly AliasGenerator _aliasGenerator = new AliasGenerator("LQ", 0);
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private readonly OrderByLifter _orderByLifter;
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#region Consts
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private const string s_visualBasicAssemblyFullName =
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"Microsoft.VisualBasic, Version=10.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a";
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private static readonly Dictionary<ExpressionType, Translator> s_translators = InitializeTranslators();
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internal const string s_entityCollectionCountPropertyName = "Count";
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internal const string s_nullableHasValuePropertyName = "HasValue";
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internal const string s_nullableValuePropertyName = "Value";
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/// <summary>
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/// Gets the name of the key column appearing in ELinq GroupBy projections
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/// </summary>
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internal const string KeyColumnName = "Key";
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/// <summary>
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/// Gets the name of the group column appearing in ELinq CQTs (used in GroupBy expressions)
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/// </summary>
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internal const string GroupColumnName = "Group";
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/// <summary>
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/// Gets the name of the parent column appearing in ELinq EntityCollection projections
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/// </summary>
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internal const string EntityCollectionOwnerColumnName = "Owner";
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/// <summary>
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/// Gets the name of the children column appearing in ELinq EntityCollection projections
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/// </summary>
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internal const string EntityCollectionElementsColumnName = "Elements";
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/// <summary>
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/// The Edm namespace name, used for canonical functions
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/// </summary>
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internal const string EdmNamespaceName = "Edm";
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#endregion
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#region Canonical Function Names
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private const string Concat = "Concat";
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private const string IndexOf = "IndexOf";
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private const string Length = "Length";
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private const string Right = "Right";
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private const string Substring = "Substring";
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private const string ToUpper = "ToUpper";
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private const string ToLower = "ToLower";
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private const string Trim = "Trim";
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private const string LTrim = "LTrim";
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private const string RTrim = "RTrim";
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private const string Reverse = "Reverse";
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private const string BitwiseAnd = "BitwiseAnd";
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private const string BitwiseOr = "BitwiseOr";
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private const string BitwiseNot = "BitwiseNot";
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private const string BitwiseXor = "BitwiseXor";
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private const string CurrentUtcDateTime = "CurrentUtcDateTime";
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private const string CurrentDateTimeOffset = "CurrentDateTimeOffset";
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private const string CurrentDateTime = "CurrentDateTime";
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private const string Year = "Year";
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private const string Month = "Month";
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private const string Day = "Day";
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private const string Hour = "Hour";
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private const string Minute = "Minute";
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private const string Second = "Second";
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private const string Millisecond = "Millisecond";
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#endregion
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#region Additional Entity function names
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private const string AsUnicode = "AsUnicode";
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private const string AsNonUnicode = "AsNonUnicode";
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#endregion
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#endregion
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#region Constructors and static initializors
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internal ExpressionConverter(Funcletizer funcletizer, Expression expression)
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{
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EntityUtil.CheckArgumentNull(funcletizer, "funcletizer");
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EntityUtil.CheckArgumentNull(expression, "expression");
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// Funcletize the expression (identify subexpressions that should be evaluated
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// locally)
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_funcletizer = funcletizer;
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expression = funcletizer.Funcletize(expression, out _recompileRequired);
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// Normalize the expression (replace obfuscated parts of the tree with simpler nodes)
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LinqExpressionNormalizer normalizer = new LinqExpressionNormalizer();
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_expression = normalizer.Visit(expression);
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_perspective = funcletizer.RootContext.Perspective;
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_bindingContext = new BindingContext();
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_ignoreInclude = 0;
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_orderByLifter = new OrderByLifter(_aliasGenerator);
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}
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// initialize translator dictionary (which support identification of translators
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// for LINQ expression node types)
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private static Dictionary<ExpressionType, Translator> InitializeTranslators()
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{
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Dictionary<ExpressionType, Translator> translators = new Dictionary<ExpressionType, Translator>();
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foreach (Translator translator in GetTranslators())
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{
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foreach (ExpressionType nodeType in translator.NodeTypes)
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{
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translators.Add(nodeType, translator);
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}
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}
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return translators;
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}
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private static IEnumerable<Translator> GetTranslators()
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{
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yield return new AndAlsoTranslator();
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yield return new OrElseTranslator();
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yield return new LessThanTranslator();
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yield return new LessThanOrEqualsTranslator();
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yield return new GreaterThanTranslator();
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yield return new GreaterThanOrEqualsTranslator();
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yield return new EqualsTranslator();
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yield return new NotEqualsTranslator();
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yield return new ConvertTranslator();
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yield return new ConstantTranslator();
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yield return new NotTranslator();
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yield return new MemberAccessTranslator();
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yield return new ParameterTranslator();
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yield return new MemberInitTranslator();
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yield return new NewTranslator();
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yield return new AddTranslator();
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yield return new ConditionalTranslator();
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yield return new DivideTranslator();
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yield return new ModuloTranslator();
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yield return new SubtractTranslator();
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yield return new MultiplyTranslator();
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yield return new NegateTranslator();
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yield return new UnaryPlusTranslator();
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yield return new MethodCallTranslator();
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yield return new CoalesceTranslator();
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yield return new AsTranslator();
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yield return new IsTranslator();
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yield return new QuoteTranslator();
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yield return new AndTranslator();
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yield return new OrTranslator();
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yield return new ExclusiveOrTranslator();
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yield return new ExtensionTranslator();
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yield return new NewArrayInitTranslator();
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yield return new ListInitTranslator();
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yield return new NotSupportedTranslator(
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ExpressionType.LeftShift,
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ExpressionType.RightShift,
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ExpressionType.ArrayLength,
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ExpressionType.ArrayIndex,
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ExpressionType.Invoke,
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ExpressionType.Lambda,
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ExpressionType.NewArrayBounds,
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ExpressionType.Power);
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}
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#endregion
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#region Properties
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private EdmItemCollection EdmItemCollection
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{
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get
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{
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return (EdmItemCollection)_funcletizer.RootContext.MetadataWorkspace.GetItemCollection(DataSpace.CSpace, true);
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}
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}
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internal DbProviderManifest ProviderManifest
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{
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get
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{
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return ((StoreItemCollection)_funcletizer.RootContext.MetadataWorkspace.GetItemCollection(DataSpace.SSpace)).StoreProviderManifest;
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}
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}
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internal System.Collections.ObjectModel.ReadOnlyCollection<KeyValuePair<ObjectParameter, QueryParameterExpression>> GetParameters()
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{
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if (null != _parameters) { return _parameters.AsReadOnly(); }
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return null;
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}
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internal MergeOption? PropagatedMergeOption { get { return _mergeOption; } }
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internal Span PropagatedSpan { get { return _span; } }
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internal Func<bool> RecompileRequired { get { return _recompileRequired; } }
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internal int IgnoreInclude { get { return _ignoreInclude; } set { _ignoreInclude = value; } }
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internal AliasGenerator AliasGenerator { get { return _aliasGenerator; } }
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#endregion
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#region Internal methods
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// Convert the LINQ expression to a CQT expression and (optional) Span information.
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// Span information will only be present if ObjectQuery instances that specify Spans
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// are referenced from the LINQ expression in a manner consistent with the Span combination
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// rules, otherwise the Span for the CQT expression will be null.
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internal DbExpression Convert()
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{
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DbExpression result = this.TranslateExpression(_expression);
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if (!TryGetSpan(result, out _span))
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{
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_span = null;
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}
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return result;
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}
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internal static bool CanFuncletizePropertyInfo(PropertyInfo propertyInfo)
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{
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return MemberAccessTranslator.CanFuncletizePropertyInfo(propertyInfo);
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}
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internal bool CanIncludeSpanInfo()
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{
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return (_ignoreInclude == 0);
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}
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#endregion
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#region Private Methods
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private void NotifyMergeOption(MergeOption mergeOption)
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{
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if (!this._mergeOption.HasValue)
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{
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this._mergeOption = mergeOption;
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}
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}
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// Requires: metadata must not be null.
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//
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// Effects: adds initializer metadata to this query context.
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//
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// Ensures that the given initializer metadata is valid within the current converter context.
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// We do not allow two incompatible structures representing the same type within a query, e.g.,
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//
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// outer.Join(inner, o => new Foo { X = o.ID }, i => new Foo { Y = i.ID }, ...
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//
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// since this introduces a discrepancy between the CLR (where comparisons between Foo are aware
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// of both X and Y) and in ELinq (where comparisons are based on the row structure only), resulting
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// in the following join predicates:
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//
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// Linq: foo1 == foo2 (which presumably amounts to foo1.X == foo2.X && foo1.Y == foo2.Y
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// ELinq: foo1.X == foo2.Y
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//
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// Similar problems occur with set operations such as Union and Concat, where one of the initialization
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// patterns may be ignored.
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//
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// This method performs an overly strict check, requiring that all initializers for a given type
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// are structurally equivalent.
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[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2301", Justification = "metadata.ClrType is not expected to be an Embedded Interop Type.")]
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internal void ValidateInitializerMetadata(InitializerMetadata metadata)
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{
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Debug.Assert(null != metadata);
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InitializerMetadata existingMetadata;
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if (_initializers != null && _initializers.TryGetValue(metadata.ClrType, out existingMetadata))
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{
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// Verify the initializers are compatible.
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if (!metadata.Equals(existingMetadata))
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{
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throw EntityUtil.NotSupported(System.Data.Entity.Strings.ELinq_UnsupportedHeterogeneousInitializers(
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ExpressionConverter.DescribeClrType(metadata.ClrType)));
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}
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}
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else
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{
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// Register the metadata so that subsequent initializers for this type can be verified.
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if (_initializers == null)
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{
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_initializers = new Dictionary<Type, InitializerMetadata>();
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}
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_initializers.Add(metadata.ClrType, metadata);
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}
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}
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private void AddParameter(QueryParameterExpression queryParameter)
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{
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if (null == _parameters)
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{
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_parameters = new List<KeyValuePair<ObjectParameter, QueryParameterExpression>>();
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}
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if (!_parameters.Select(p => p.Value).Contains(queryParameter))
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{
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ObjectParameter parameter = new ObjectParameter(queryParameter.ParameterReference.ParameterName, queryParameter.Type);
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_parameters.Add(new KeyValuePair<ObjectParameter, QueryParameterExpression>(parameter, queryParameter));
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}
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}
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private bool IsQueryRoot(Expression Expression)
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{
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//
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// An expression is the query root if it was the expression used
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// when constructing this converter.
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//
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return object.ReferenceEquals(_expression, Expression);
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}
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#region Span Mapping maintenance methods
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/// <summary>
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/// Adds a new mapping from DbExpression => Span information for the specified expression,
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/// after first ensuring that the mapping dictionary has been instantiated.
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/// </summary>
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/// <param name="expression">The expression for which Span information should be added</param>
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/// <param name="span">
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/// The Span information, which may be <c>null</c>.
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/// If <c>null</c>, no attempt is made to update the dictionary of span mappings.
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/// </param>
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/// <returns>The original <paramref name="expression"/> argument, to allow <c>return AddSpanMapping(expression, span)</c> scenarios</returns>
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private DbExpression AddSpanMapping(DbExpression expression, Span span)
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{
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if (span != null && this.CanIncludeSpanInfo())
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{
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if (null == _spanMappings)
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{
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_spanMappings = new Dictionary<DbExpression, Span>();
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}
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Span storedSpan = null;
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if (_spanMappings.TryGetValue(expression, out storedSpan))
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{
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foreach (Span.SpanPath sp in span.SpanList)
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{
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storedSpan.AddSpanPath(sp);
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}
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_spanMappings[expression] = storedSpan;
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}
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else
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{
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_spanMappings[expression] = span;
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}
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}
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return expression;
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}
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/// <summary>
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/// Attempts to retrieve Span information for the specified DbExpression.
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/// </summary>
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/// <param name="expression">The expression for which Span information should be retrieved.</param>
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/// <param name="span">Will contain the Span information for the specified expression if it is present in the Span mapping dictionary.</param>
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/// <returns><c>true</c> if Span information was retrieved for the specified expression and <paramref name="span"/> now contains this information; otherwise <c>false</c>.</returns>
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private bool TryGetSpan(DbExpression expression, out Span span)
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{
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if (_spanMappings != null)
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{
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return _spanMappings.TryGetValue(expression, out span);
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}
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span = null;
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return false;
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}
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/// <summary>
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/// Removes the Span mapping entry for the specified <paramref name="from"/> expression,
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/// and creates a new entry for the specified <paramref name="to"/> expression that maps
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/// to the <paramref name="from"/> expression's original Span information. If no Span
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/// information is present for the specified <paramref name="from"/> expression then no
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/// changes are made to the Span mapping dictionary.
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/// </summary>
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/// <param name="from">The expression from which to take Span information</param>
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/// <param name="to">The expression to which the Span information should be applied</param>
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private void ApplySpanMapping(DbExpression from, DbExpression to)
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{
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Span argumentSpan;
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if (TryGetSpan(from, out argumentSpan))
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{
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AddSpanMapping(to, argumentSpan);
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}
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}
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/// <summary>
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/// Unifies the Span information from the specified <paramref name="left"/> and <paramref name="right"/>
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/// expressions, and applies it to the specified <paramref name="to"/> expression. Unification proceeds
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/// as follows:
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/// - If neither <paramref name="left"/> nor <paramref name="right"/> have Span information, no changes are made
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/// - If one of <paramref name="left"/> or <paramref name="right"/> has Span information, that single Span information
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/// entry is removed from the Span mapping dictionary and used to create a new entry that maps from the <paramref name="to"/>
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/// expression to the Span information.
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/// - If both <paramref name="left"/> and <paramref name="right"/> have Span information, both entries are removed
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/// from the Span mapping dictionary, a new Span is created that contains the union of the original Spans, and
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/// a new entry is added to the dictionary that maps from <paramref name="to"/> expression to this new Span.
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/// </summary>
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/// <param name="left">The first expression argument</param>
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/// <param name="right">The second expression argument</param>
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/// <param name="to">The result expression</param>
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private void UnifySpanMappings(DbExpression left, DbExpression right, DbExpression to)
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{
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Span leftSpan = null;
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Span rightSpan = null;
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bool hasLeftSpan = TryGetSpan(left, out leftSpan);
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bool hasRightSpan = TryGetSpan(right, out rightSpan);
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if (!hasLeftSpan && !hasRightSpan)
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{
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return;
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}
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Debug.Assert(leftSpan != null || rightSpan != null, "Span mappings contain null?");
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AddSpanMapping(to, Span.CopyUnion(leftSpan, rightSpan));
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}
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#endregion
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// The following methods correspond to query builder methods on ObjectQuery
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// and MUST be called by expression translators (instead of calling the equivalent
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// CommandTree.CreateXxExpression methods) to ensure that Span information flows
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// correctly to the root of the Command Tree as it is constructed by converting
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// the LINQ expression tree. Each method correctly maintains a Span mapping (if required)
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// for its resulting expression, based on the Span mappings of its argument expression(s).
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private DbDistinctExpression Distinct(DbExpression argument)
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{
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DbDistinctExpression retExpr = argument.Distinct();
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ApplySpanMapping(argument, retExpr);
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return retExpr;
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}
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private DbExceptExpression Except(DbExpression left, DbExpression right)
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{
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DbExceptExpression retExpr = left.Except(right);
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ApplySpanMapping(left, retExpr);
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return retExpr;
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}
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private DbExpression Filter(DbExpressionBinding input, DbExpression predicate)
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{
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DbExpression retExpr = _orderByLifter.Filter(input, predicate);
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ApplySpanMapping(input.Expression, retExpr);
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return retExpr;
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}
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private DbIntersectExpression Intersect(DbExpression left, DbExpression right)
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{
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DbIntersectExpression retExpr = left.Intersect(right);
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UnifySpanMappings(left, right, retExpr);
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return retExpr;
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}
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private DbExpression Limit(DbExpression argument, DbExpression limit)
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{
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DbExpression retExpr = _orderByLifter.Limit(argument, limit);
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ApplySpanMapping(argument, retExpr);
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return retExpr;
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}
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private DbExpression OfType(DbExpression argument, TypeUsage ofType)
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{
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DbExpression retExpr = _orderByLifter.OfType(argument, ofType);
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ApplySpanMapping(argument, retExpr);
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return retExpr;
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}
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private DbExpression Project(DbExpressionBinding input, DbExpression projection)
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{
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DbExpression retExpr = _orderByLifter.Project(input, projection);
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// For identity projection only, the Span is preserved
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if (projection.ExpressionKind == DbExpressionKind.VariableReference &&
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((DbVariableReferenceExpression)projection).VariableName.Equals(input.VariableName, StringComparison.Ordinal))
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{
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ApplySpanMapping(input.Expression, retExpr);
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}
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return retExpr;
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}
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private DbSortExpression Sort(DbExpressionBinding input, IList<DbSortClause> keys)
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{
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DbSortExpression retExpr = input.Sort(keys);
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ApplySpanMapping(input.Expression, retExpr);
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return retExpr;
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}
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|
|
private DbExpression Skip(DbExpressionBinding input, DbExpression skipCount)
|
|
{
|
|
DbExpression retExpr = _orderByLifter.Skip(input, skipCount);
|
|
ApplySpanMapping(input.Expression, retExpr);
|
|
return retExpr;
|
|
}
|
|
|
|
private DbUnionAllExpression UnionAll(DbExpression left, DbExpression right)
|
|
{
|
|
DbUnionAllExpression retExpr = left.UnionAll(right);
|
|
UnifySpanMappings(left, right, retExpr);
|
|
return retExpr;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Gets the target type for a CQT cast operation.
|
|
/// </summary>
|
|
/// <returns>Appropriate type usage, or null if this is a "no-op"</returns>
|
|
private TypeUsage GetCastTargetType(TypeUsage fromType, Type toClrType, Type fromClrType, bool preserveCastForDateTime)
|
|
{
|
|
// An inlined ObjectQuery or an IOrderedQueryable expression being cast to IQueryable for use in a sequence method is a no-op.
|
|
if(fromClrType != null &&
|
|
fromClrType.IsGenericType && toClrType.IsGenericType &&
|
|
(fromClrType.GetGenericTypeDefinition() == typeof(ObjectQuery<>) || fromClrType.GetGenericTypeDefinition() == typeof(IOrderedQueryable<>)) &&
|
|
(toClrType.GetGenericTypeDefinition() == typeof(IQueryable<>) || toClrType.GetGenericTypeDefinition() == typeof(IOrderedQueryable<>)) &&
|
|
fromClrType.GetGenericArguments()[0] == toClrType.GetGenericArguments()[0])
|
|
{
|
|
return null;
|
|
}
|
|
|
|
// If the types are the same or the fromType is assignable to toType, return null
|
|
// (indicating no cast is required)
|
|
TypeUsage toType;
|
|
if (TryGetValueLayerType(toClrType, out toType) && CanOmitCast(fromType, toType, preserveCastForDateTime))
|
|
{
|
|
return null;
|
|
}
|
|
|
|
// Check that the cast is supported and adjust the target type as necessary.
|
|
toType = ValidateAndAdjustCastTypes(toType, fromType, toClrType, fromClrType);
|
|
|
|
return toType;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Check that the given cast specification is supported and if necessary adjust target type (for instance
|
|
/// add precision and scale for Integral -> Decimal casts)
|
|
/// </summary>
|
|
private static TypeUsage ValidateAndAdjustCastTypes(TypeUsage toType, TypeUsage fromType, Type toClrType, Type fromClrType)
|
|
{
|
|
// only support primitives if real casting is involved
|
|
if (toType == null || !TypeSemantics.IsScalarType(toType) || !TypeSemantics.IsScalarType(fromType))
|
|
{
|
|
throw EntityUtil.NotSupported(System.Data.Entity.Strings.ELinq_UnsupportedCast(DescribeClrType(fromClrType), DescribeClrType(toClrType)));
|
|
}
|
|
|
|
PrimitiveTypeKind fromTypeKind = Helper.AsPrimitive(fromType.EdmType).PrimitiveTypeKind;
|
|
PrimitiveTypeKind toTypeKind = Helper.AsPrimitive(toType.EdmType).PrimitiveTypeKind;
|
|
|
|
if (toTypeKind == PrimitiveTypeKind.Decimal)
|
|
{
|
|
// Can't figure out the right precision and scale for decimal, so only accept integer types
|
|
switch (fromTypeKind)
|
|
{
|
|
case PrimitiveTypeKind.Byte:
|
|
case PrimitiveTypeKind.Int16:
|
|
case PrimitiveTypeKind.Int32:
|
|
case PrimitiveTypeKind.Int64:
|
|
case PrimitiveTypeKind.SByte:
|
|
// adjust precision and scale to ensure sufficient width
|
|
toType = TypeUsage.CreateDecimalTypeUsage((PrimitiveType)toType.EdmType, 19, 0);
|
|
break;
|
|
default:
|
|
throw EntityUtil.NotSupported(System.Data.Entity.Strings.ELinq_UnsupportedCastToDecimal);
|
|
}
|
|
}
|
|
|
|
return toType;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Determines if an instance of fromType can be assigned to an instance of toType using
|
|
/// CLR semantics. in case of primitive type, it must rely on identity since unboxing primitive requires
|
|
/// exact match. for nominal types, rely on subtyping.
|
|
/// </summary>
|
|
private static bool CanOmitCast(TypeUsage fromType, TypeUsage toType, bool preserveCastForDateTime)
|
|
{
|
|
bool isPrimitiveType = TypeSemantics.IsPrimitiveType(fromType);
|
|
|
|
//SQLBUDT #573573: This is to allow for a workaround on Katmai via explicit casting by the user.
|
|
// The issue is that SqlServer's type Date maps to Edm.DateTime, same as SqlServer's DateTime and SmallDateTime.
|
|
// However the conversion is not possible for all values of Date.
|
|
|
|
//Note: we could also call here TypeSemantics.IsPrimitiveType(TypeUsage type, PrimitiveTypeKind primitiveTypeKind),
|
|
// but that checks again whether the type is primitive
|
|
if (isPrimitiveType && preserveCastForDateTime && ((PrimitiveType)fromType.EdmType).PrimitiveTypeKind == PrimitiveTypeKind.DateTime)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
if (TypeUsageEquals(fromType, toType))
|
|
{
|
|
return true;
|
|
}
|
|
|
|
if (isPrimitiveType)
|
|
{
|
|
return fromType.EdmType.EdmEquals(toType.EdmType);
|
|
}
|
|
|
|
return TypeSemantics.IsSubTypeOf(fromType, toType);
|
|
}
|
|
|
|
/// <summary>
|
|
/// Gets the target type for an Is or As expression.
|
|
/// </summary>
|
|
/// <param name="fromType">Input type in model metadata.</param>
|
|
/// <param name="toClrType">Test or return type.</param>
|
|
/// <param name="operationType">Type of operation; used in error reporting.</param>
|
|
/// <param name="fromClrType">Input type in CLR metadata.</param>
|
|
/// <returns>Appropriate target type usage.</returns>
|
|
private TypeUsage GetIsOrAsTargetType(TypeUsage fromType, ExpressionType operationType, Type toClrType, Type fromClrType)
|
|
{
|
|
Debug.Assert(operationType == ExpressionType.TypeAs || operationType == ExpressionType.TypeIs);
|
|
|
|
// Interpret all type information
|
|
TypeUsage toType;
|
|
if (!this.TryGetValueLayerType(toClrType, out toType) ||
|
|
(!TypeSemantics.IsEntityType(toType) &&
|
|
!TypeSemantics.IsComplexType(toType)))
|
|
{
|
|
throw EntityUtil.NotSupported(System.Data.Entity.Strings.ELinq_UnsupportedIsOrAs(operationType,
|
|
DescribeClrType(fromClrType), DescribeClrType(toClrType)));
|
|
}
|
|
|
|
return toType;
|
|
}
|
|
|
|
// requires: inlineQuery is not null and inlineQuery is Entity-SQL query
|
|
// effects: interprets the given query as an inline query in the current expression and unites
|
|
// the current query context with the context for the inline query. If the given query specifies
|
|
// span information, then an entry is added to the span mapping dictionary from the CQT expression
|
|
// that is the root of the inline query, to the span information that was present in the inline
|
|
// query's Span property.
|
|
private DbExpression TranslateInlineQueryOfT(ObjectQuery inlineQuery)
|
|
{
|
|
if (!object.ReferenceEquals(_funcletizer.RootContext, inlineQuery.QueryState.ObjectContext))
|
|
{
|
|
throw EntityUtil.NotSupported(System.Data.Entity.Strings.ELinq_UnsupportedDifferentContexts);
|
|
}
|
|
|
|
// Check if the inline query has been encountered so far. If so, we don't need to
|
|
// include its parameters again. We do however need to translate it to a new
|
|
// DbExpression instance since the expressions may be tagged with span information
|
|
// and we don't want to mistakenly apply the directive to the wrong part of the query.
|
|
if (null == _inlineEntitySqlQueries)
|
|
{
|
|
_inlineEntitySqlQueries = new HashSet<ObjectQuery>();
|
|
}
|
|
bool isNewInlineQuery = _inlineEntitySqlQueries.Add(inlineQuery);
|
|
|
|
// The ObjectQuery should be Entity-SQL-based at this point. All other query types are currently
|
|
// inlined.
|
|
EntitySqlQueryState esqlState = (EntitySqlQueryState)inlineQuery.QueryState;
|
|
|
|
// We will produce the translated expression by parsing the Entity-SQL query text.
|
|
DbExpression resultExpression = null;
|
|
|
|
// If we are not converting a compiled query, or the referenced Entity-SQL ObjectQuery
|
|
// does not have parameters (and so no parameter references can be in the parsed tree)
|
|
// then the Entity-SQL can be parsed directly using the conversion command tree.
|
|
ObjectParameterCollection objectParameters = inlineQuery.QueryState.Parameters;
|
|
if (!_funcletizer.IsCompiledQuery ||
|
|
objectParameters == null ||
|
|
objectParameters.Count == 0)
|
|
{
|
|
// Add parameters if they exist and we haven't yet encountered this inline query.
|
|
if (isNewInlineQuery && objectParameters != null)
|
|
{
|
|
// Copy the parameters into the aggregated parameter collection - this will result
|
|
// in an exception if any duplicate parameter names are encountered.
|
|
if (this._parameters == null)
|
|
{
|
|
this._parameters = new List<KeyValuePair<ObjectParameter, QueryParameterExpression>>();
|
|
}
|
|
foreach (ObjectParameter prm in inlineQuery.QueryState.Parameters)
|
|
{
|
|
this._parameters.Add(new KeyValuePair<ObjectParameter, QueryParameterExpression>(prm.ShallowCopy(), null));
|
|
}
|
|
}
|
|
|
|
resultExpression = esqlState.Parse();
|
|
}
|
|
else
|
|
{
|
|
// We are converting a compiled query and parameters are present on the referenced ObjectQuery.
|
|
// The set of parameters available to a compiled query is fixed (so that adding/removing parameters
|
|
// to/from a referenced ObjectQuery does not invalidate the compiled query's execution plan), so the
|
|
// referenced ObjectQuery will be fully inlined by replacing each parameter reference with a
|
|
// DbConstantExpression containing the value of the referenced parameter.
|
|
resultExpression = esqlState.Parse();
|
|
resultExpression = ParameterReferenceRemover.RemoveParameterReferences(resultExpression, objectParameters);
|
|
}
|
|
|
|
return resultExpression;
|
|
}
|
|
|
|
private class ParameterReferenceRemover : DefaultExpressionVisitor
|
|
{
|
|
internal static DbExpression RemoveParameterReferences(DbExpression expression, ObjectParameterCollection availableParameters)
|
|
{
|
|
ParameterReferenceRemover remover = new ParameterReferenceRemover(availableParameters);
|
|
return remover.VisitExpression(expression);
|
|
}
|
|
|
|
private readonly ObjectParameterCollection objectParameters;
|
|
private ParameterReferenceRemover(ObjectParameterCollection availableParams)
|
|
: base()
|
|
{
|
|
Debug.Assert(availableParams != null, "Parameter collection cannot be null");
|
|
|
|
this.objectParameters = availableParams;
|
|
}
|
|
|
|
public override DbExpression Visit(DbParameterReferenceExpression expression)
|
|
{
|
|
if (this.objectParameters.Contains(expression.ParameterName))
|
|
{
|
|
// A DbNullExpression is required for null values; DbConstantExpression otherwise.
|
|
ObjectParameter objParam = objectParameters[expression.ParameterName];
|
|
if (null == objParam.Value)
|
|
{
|
|
return DbExpressionBuilder.Null(expression.ResultType);
|
|
}
|
|
else
|
|
{
|
|
// This will throw if the value is incompatible with the result type.
|
|
return DbExpressionBuilder.Constant(expression.ResultType, objParam.Value);
|
|
}
|
|
}
|
|
return expression;
|
|
}
|
|
}
|
|
|
|
// creates a CQT cast expression given the source and target CLR type
|
|
private DbExpression CreateCastExpression(DbExpression source, Type toClrType, Type fromClrType)
|
|
{
|
|
// see if the source can be normalized as a set
|
|
DbExpression setSource = NormalizeSetSource(source);
|
|
if (!Object.ReferenceEquals(source, setSource))
|
|
{
|
|
// if the resulting cast is a no-op (no either kind is supported
|
|
// for set sources), yield the source
|
|
if (null == GetCastTargetType(setSource.ResultType, toClrType, fromClrType, true))
|
|
{
|
|
return source;
|
|
}
|
|
}
|
|
|
|
// try to find the appropriate target target for the cast
|
|
TypeUsage toType = GetCastTargetType(source.ResultType, toClrType, fromClrType, true);
|
|
if (null == toType)
|
|
{
|
|
// null indicates a no-op cast (from the perspective of the model)
|
|
return source;
|
|
}
|
|
|
|
return source.CastTo(toType);
|
|
}
|
|
|
|
// Utility translator method for lambda expressions. Given a lambda expression and its translated
|
|
// inputs, translates the lambda expression, assuming the input is a collection
|
|
private DbExpression TranslateLambda(LambdaExpression lambda, DbExpression input, out DbExpressionBinding binding)
|
|
{
|
|
input = NormalizeSetSource(input);
|
|
|
|
// create binding context for this lambda expression
|
|
binding = input.BindAs(_aliasGenerator.Next());
|
|
|
|
return TranslateLambda(lambda, binding.Variable);
|
|
}
|
|
|
|
// Utility translator method for lambda expressions. Given a lambda expression and its translated
|
|
// inputs, translates the lambda expression, assuming the input is a collection
|
|
private DbExpression TranslateLambda(LambdaExpression lambda, DbExpression input, string bindingName, out DbExpressionBinding binding)
|
|
{
|
|
input = NormalizeSetSource(input);
|
|
|
|
// create binding context for this lambda expression
|
|
binding = input.BindAs(bindingName);
|
|
|
|
return TranslateLambda(lambda, binding.Variable);
|
|
}
|
|
|
|
// Utility translator method for lambda expressions that are part of group by. Given a lambda expression and its translated
|
|
// inputs, translates the lambda expression, assuming the input needs to be used as a grouping input
|
|
private DbExpression TranslateLambda(LambdaExpression lambda, DbExpression input, out DbGroupExpressionBinding binding)
|
|
{
|
|
input = NormalizeSetSource(input);
|
|
|
|
// create binding context for this lambda expression
|
|
string alias = _aliasGenerator.Next();
|
|
binding = input.GroupBindAs(alias, string.Format(CultureInfo.InvariantCulture, "Group{0}", alias));
|
|
|
|
return TranslateLambda(lambda, binding.Variable);
|
|
}
|
|
|
|
// Utility translator method for lambda expressions. Given a lambda expression and its translated
|
|
// inputs, translates the lambda expression
|
|
private DbExpression TranslateLambda(LambdaExpression lambda, DbExpression input)
|
|
{
|
|
Binding scopeBinding = new Binding(lambda.Parameters[0], input);
|
|
|
|
// push the binding scope
|
|
_bindingContext.PushBindingScope(scopeBinding);
|
|
|
|
// translate expression within this binding scope
|
|
#if DEBUG
|
|
int preValue = _ignoreInclude;
|
|
#endif
|
|
_ignoreInclude++;
|
|
DbExpression result = TranslateExpression(lambda.Body);
|
|
_ignoreInclude--;
|
|
#if DEBUG
|
|
Debug.Assert(preValue == _ignoreInclude);
|
|
#endif
|
|
|
|
// pop binding scope
|
|
_bindingContext.PopBindingScope();
|
|
|
|
return result;
|
|
}
|
|
|
|
// effects: unwraps any "structured" set sources such as IGrouping instances
|
|
// (which acts as both a set and a structure containing a property)
|
|
private DbExpression NormalizeSetSource(DbExpression input)
|
|
{
|
|
Debug.Assert(null != input);
|
|
|
|
// If input looks like "select x from (...) as x", rewrite it as "(...)".
|
|
// If input has span information attached to to it then leave it as is, otherwise
|
|
// span info will be lost.
|
|
Span span;
|
|
if (input.ExpressionKind == DbExpressionKind.Project && !TryGetSpan(input, out span))
|
|
{
|
|
var project = (DbProjectExpression)input;
|
|
if (project.Projection == project.Input.Variable)
|
|
{
|
|
input = project.Input.Expression;
|
|
}
|
|
}
|
|
|
|
// determine if the lambda input is an IGrouping or EntityCollection that needs to be unwrapped
|
|
InitializerMetadata initializerMetadata;
|
|
if (InitializerMetadata.TryGetInitializerMetadata(input.ResultType, out initializerMetadata))
|
|
{
|
|
if (initializerMetadata.Kind == InitializerMetadataKind.Grouping)
|
|
{
|
|
// for group by, redirect the binding to the group (rather than the property)
|
|
input = input.Property(ExpressionConverter.GroupColumnName);
|
|
}
|
|
else if (initializerMetadata.Kind == InitializerMetadataKind.EntityCollection)
|
|
{
|
|
// for entity collection, redirect the binding to the children
|
|
input = input.Property(ExpressionConverter.EntityCollectionElementsColumnName);
|
|
}
|
|
}
|
|
return input;
|
|
}
|
|
|
|
// Given a method call expression, returns the given lambda argument (unwrapping quote or closure references where
|
|
// necessary)
|
|
private LambdaExpression GetLambdaExpression(MethodCallExpression callExpression, int argumentOrdinal)
|
|
{
|
|
Expression argument = callExpression.Arguments[argumentOrdinal];
|
|
return (LambdaExpression)GetLambdaExpression(argument);
|
|
}
|
|
|
|
private Expression GetLambdaExpression(Expression argument)
|
|
{
|
|
if (ExpressionType.Lambda == argument.NodeType)
|
|
{
|
|
return argument;
|
|
}
|
|
else if (ExpressionType.Quote == argument.NodeType)
|
|
{
|
|
return GetLambdaExpression(((UnaryExpression)argument).Operand);
|
|
}
|
|
|
|
throw EntityUtil.InternalError(EntityUtil.InternalErrorCode.UnexpectedLinqLambdaExpressionFormat);
|
|
}
|
|
|
|
// Translate a LINQ expression acting as a set input to a CQT expression
|
|
private DbExpression TranslateSet(Expression linq)
|
|
{
|
|
return NormalizeSetSource(TranslateExpression(linq));
|
|
}
|
|
|
|
// Translate a LINQ expression to a CQT expression.
|
|
private DbExpression TranslateExpression(Expression linq)
|
|
{
|
|
Debug.Assert(null != linq);
|
|
|
|
DbExpression result;
|
|
if (!_bindingContext.TryGetBoundExpression(linq, out result))
|
|
{
|
|
// translate to a CQT expression
|
|
Translator translator;
|
|
if (s_translators.TryGetValue(linq.NodeType, out translator))
|
|
{
|
|
result = translator.Translate(this, linq);
|
|
}
|
|
else
|
|
{
|
|
throw EntityUtil.InternalError(EntityUtil.InternalErrorCode.UnknownLinqNodeType, -1,
|
|
linq.NodeType.ToString());
|
|
}
|
|
}
|
|
return result;
|
|
}
|
|
|
|
// Cast expression to align types between CQT and eLINQ
|
|
private DbExpression AlignTypes(DbExpression cqt, Type toClrType)
|
|
{
|
|
Type fromClrType = null; // not used in this code path
|
|
TypeUsage toType = GetCastTargetType(cqt.ResultType, toClrType, fromClrType, false);
|
|
if (null != toType)
|
|
{
|
|
return cqt.CastTo(toType);
|
|
}
|
|
else
|
|
{
|
|
return cqt;
|
|
}
|
|
}
|
|
|
|
// Determines whether the given type is supported for materialization
|
|
private void CheckInitializerType(Type type)
|
|
{
|
|
// nominal types are not supported
|
|
TypeUsage typeUsage;
|
|
if (_funcletizer.RootContext.Perspective.TryGetType(type, out typeUsage))
|
|
{
|
|
BuiltInTypeKind typeKind = typeUsage.EdmType.BuiltInTypeKind;
|
|
if (BuiltInTypeKind.EntityType == typeKind ||
|
|
BuiltInTypeKind.ComplexType == typeKind)
|
|
{
|
|
throw EntityUtil.NotSupported(System.Data.Entity.Strings.ELinq_UnsupportedNominalType(
|
|
typeUsage.EdmType.FullName));
|
|
}
|
|
}
|
|
|
|
// types implementing IEnumerable are not supported
|
|
if (TypeSystem.IsSequenceType(type))
|
|
{
|
|
throw EntityUtil.NotSupported(System.Data.Entity.Strings.ELinq_UnsupportedEnumerableType(
|
|
DescribeClrType(type)));
|
|
}
|
|
}
|
|
|
|
|
|
// requires: Left and right are non-null.
|
|
// effects: Determines if the given types are equivalent, ignoring facets. In
|
|
// the case of primitive types, consider types equivalent if their kinds are
|
|
// equivalent.
|
|
// comments: This method is useful in cases where the type facets or specific
|
|
// store primitive type are not reliably known, e.g. when the EDM type is determined
|
|
// from the CLR type
|
|
private static bool TypeUsageEquals(TypeUsage left, TypeUsage right)
|
|
{
|
|
Debug.Assert(null != left);
|
|
Debug.Assert(null != right);
|
|
if (left.EdmType.EdmEquals(right.EdmType)) { return true; }
|
|
|
|
// compare element types for collection
|
|
if (BuiltInTypeKind.CollectionType == left.EdmType.BuiltInTypeKind &&
|
|
BuiltInTypeKind.CollectionType == right.EdmType.BuiltInTypeKind)
|
|
{
|
|
return TypeUsageEquals(
|
|
((CollectionType)left.EdmType).TypeUsage,
|
|
((CollectionType)right.EdmType).TypeUsage);
|
|
}
|
|
|
|
// special case for primitive types
|
|
if (BuiltInTypeKind.PrimitiveType == left.EdmType.BuiltInTypeKind &&
|
|
BuiltInTypeKind.PrimitiveType == right.EdmType.BuiltInTypeKind)
|
|
{
|
|
// since LINQ expressions cannot indicate model types directly, we must
|
|
// consider types equivalent if they match on the given CLR equivalent
|
|
// types (consider the Xml and String primitive types)
|
|
return ((PrimitiveType)left.EdmType).ClrEquivalentType.Equals(
|
|
((PrimitiveType)right.EdmType).ClrEquivalentType);
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
private TypeUsage GetValueLayerType(Type linqType)
|
|
{
|
|
TypeUsage type;
|
|
if (!TryGetValueLayerType(linqType, out type))
|
|
{
|
|
throw EntityUtil.NotSupported(System.Data.Entity.Strings.ELinq_UnsupportedType(linqType));
|
|
}
|
|
return type;
|
|
}
|
|
|
|
// Determine C-Space equivalent type for linqType
|
|
private bool TryGetValueLayerType(Type linqType, out TypeUsage type)
|
|
{
|
|
// Remove nullable
|
|
Type nonNullableType = TypeSystem.GetNonNullableType(linqType);
|
|
|
|
// Enum types are only supported for EDM V3 and higher, do not force loading
|
|
// enum types for previous versions of EDM
|
|
if (nonNullableType.IsEnum && this.EdmItemCollection.EdmVersion < XmlConstants.EdmVersionForV3)
|
|
{
|
|
nonNullableType = nonNullableType.GetEnumUnderlyingType();
|
|
}
|
|
|
|
// See if this is a primitive type
|
|
PrimitiveTypeKind primitiveTypeKind;
|
|
if (ClrProviderManifest.Instance.TryGetPrimitiveTypeKind(nonNullableType, out primitiveTypeKind))
|
|
{
|
|
type = EdmProviderManifest.Instance.GetCanonicalModelTypeUsage(primitiveTypeKind);
|
|
return true;
|
|
}
|
|
|
|
// See if this is a collection type (if so, recursively resolve)
|
|
Type elementType = TypeSystem.GetElementType(nonNullableType);
|
|
if (elementType != nonNullableType)
|
|
{
|
|
TypeUsage elementTypeUsage;
|
|
if (TryGetValueLayerType(elementType, out elementTypeUsage))
|
|
{
|
|
type = TypeHelpers.CreateCollectionTypeUsage(elementTypeUsage);
|
|
return true;
|
|
}
|
|
}
|
|
|
|
// Ensure the metadata for this object type is loaded
|
|
_perspective.MetadataWorkspace.ImplicitLoadAssemblyForType(linqType, null);
|
|
|
|
if(!_perspective.TryGetTypeByName(nonNullableType.FullName, false, out type))
|
|
{
|
|
// If the user is casting to a type that is not a model type or a primitive type it can be a cast to an enum that
|
|
// is not in the model. In that case we use the underlying enum type.
|
|
// Note that if the underlying type is not any of the EF primitive types we will fail with and InvalidCastException.
|
|
// This is consistent with what we would do when seeing a cast to a primitive type that is not a EF valid primitive
|
|
// type (e.g. ulong).
|
|
if(nonNullableType.IsEnum && ClrProviderManifest.Instance.TryGetPrimitiveTypeKind(nonNullableType.GetEnumUnderlyingType(), out primitiveTypeKind))
|
|
{
|
|
type = EdmProviderManifest.Instance.GetCanonicalModelTypeUsage(primitiveTypeKind);
|
|
}
|
|
}
|
|
|
|
return type != null;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Utility method validating type for comparison ops (isNull, equals, etc.).
|
|
/// Only primitive types, entity types, and simple row types (no IGrouping/EntityCollection) are
|
|
/// supported.
|
|
/// </summary>
|
|
private static void VerifyTypeSupportedForComparison(Type clrType, TypeUsage edmType, Stack<EdmMember> memberPath)
|
|
{
|
|
// NOTE: due to bug in null handling for complex types, complex types are currently not supported
|
|
// for comparisons (see SQL BU 543956)
|
|
switch (edmType.EdmType.BuiltInTypeKind)
|
|
{
|
|
case BuiltInTypeKind.PrimitiveType:
|
|
case BuiltInTypeKind.EnumType:
|
|
case BuiltInTypeKind.EntityType:
|
|
case BuiltInTypeKind.RefType:
|
|
return;
|
|
case BuiltInTypeKind.RowType:
|
|
{
|
|
InitializerMetadata initializerMetadata;
|
|
if (!InitializerMetadata.TryGetInitializerMetadata(edmType, out initializerMetadata) ||
|
|
initializerMetadata.Kind == InitializerMetadataKind.ProjectionInitializer ||
|
|
initializerMetadata.Kind == InitializerMetadataKind.ProjectionNew)
|
|
{
|
|
VerifyRowTypeSupportedForComparison(clrType, (RowType)edmType.EdmType, memberPath);
|
|
return;
|
|
}
|
|
break;
|
|
}
|
|
default:
|
|
break;
|
|
}
|
|
if (null == memberPath)
|
|
{
|
|
throw EntityUtil.NotSupported(Strings.ELinq_UnsupportedComparison(DescribeClrType(clrType)));
|
|
}
|
|
else
|
|
{
|
|
// build up description of member path
|
|
StringBuilder memberPathDescription = new StringBuilder();
|
|
foreach (EdmMember member in memberPath)
|
|
{
|
|
memberPathDescription.Append(Strings.ELinq_UnsupportedRowMemberComparison(member.Name));
|
|
}
|
|
memberPathDescription.Append(Strings.ELinq_UnsupportedRowTypeComparison(DescribeClrType(clrType)));
|
|
throw EntityUtil.NotSupported(Strings.ELinq_UnsupportedRowComparison(memberPathDescription.ToString()));
|
|
}
|
|
}
|
|
|
|
private static void VerifyRowTypeSupportedForComparison(Type clrType, RowType rowType, Stack<EdmMember> memberPath)
|
|
{
|
|
foreach (EdmMember member in rowType.Properties)
|
|
{
|
|
if (null == memberPath)
|
|
{
|
|
memberPath = new Stack<EdmMember>();
|
|
}
|
|
memberPath.Push(member);
|
|
VerifyTypeSupportedForComparison(clrType, member.TypeUsage, memberPath);
|
|
memberPath.Pop();
|
|
}
|
|
}
|
|
|
|
/// <summary>
|
|
/// Describe type for exception message.
|
|
/// </summary>
|
|
internal static string DescribeClrType(Type clrType)
|
|
{
|
|
string clrTypeName = clrType.Name;
|
|
// Yes, this is a heuristic... just a best effort way of getting
|
|
// a reasonable exception message
|
|
if (IsCSharpGeneratedClass(clrTypeName, "DisplayClass") ||
|
|
IsVBGeneratedClass(clrTypeName, "Closure"))
|
|
{
|
|
return Strings.ELinq_ClosureType;
|
|
}
|
|
if (IsCSharpGeneratedClass(clrTypeName, "AnonymousType") ||
|
|
IsVBGeneratedClass(clrTypeName, "AnonymousType"))
|
|
{
|
|
return Strings.ELinq_AnonymousType;
|
|
}
|
|
|
|
string returnName = string.Empty;
|
|
if (!String.IsNullOrEmpty(clrType.Namespace))
|
|
{
|
|
returnName += clrType.Namespace + ".";
|
|
}
|
|
returnName += clrType.Name;
|
|
return returnName;
|
|
}
|
|
|
|
private static bool IsCSharpGeneratedClass(string typeName, string pattern)
|
|
{
|
|
return typeName.Contains("<>") && typeName.Contains("__") && typeName.Contains(pattern);
|
|
}
|
|
|
|
private static bool IsVBGeneratedClass(string typeName, string pattern)
|
|
{
|
|
return typeName.Contains("_") && typeName.Contains("$") && typeName.Contains(pattern);
|
|
}
|
|
|
|
/// <summary>
|
|
/// Creates an implementation of IsNull. Throws exception when operand type is not supported.
|
|
/// </summary>
|
|
private DbExpression CreateIsNullExpression(DbExpression operand, Type operandClrType)
|
|
{
|
|
VerifyTypeSupportedForComparison(operandClrType, operand.ResultType, null);
|
|
return operand.IsNull();
|
|
}
|
|
|
|
/// <summary>
|
|
/// Creates an implementation of equals using the given pattern. Throws exception when argument types
|
|
/// are not supported for equals comparison.
|
|
/// </summary>
|
|
private DbExpression CreateEqualsExpression(DbExpression left, DbExpression right, EqualsPattern pattern, Type leftClrType, Type rightClrType)
|
|
{
|
|
VerifyTypeSupportedForComparison(leftClrType, left.ResultType, null);
|
|
VerifyTypeSupportedForComparison(rightClrType, right.ResultType, null);
|
|
|
|
//For Ref Type comparison, check whether they refer to compatible Entity Types.
|
|
TypeUsage leftType = left.ResultType;
|
|
TypeUsage rightType = right.ResultType;
|
|
if (leftType.EdmType.BuiltInTypeKind == BuiltInTypeKind.RefType && rightType.EdmType.BuiltInTypeKind == BuiltInTypeKind.RefType)
|
|
{
|
|
TypeUsage commonType;
|
|
if (!TypeSemantics.TryGetCommonType(leftType, rightType, out commonType))
|
|
{
|
|
RefType leftRefType = left.ResultType.EdmType as RefType;
|
|
RefType rightRefType = right.ResultType.EdmType as RefType;
|
|
throw EntityUtil.NotSupported(Strings.ELinq_UnsupportedRefComparison(leftRefType.ElementType.FullName, rightRefType.ElementType.FullName));
|
|
}
|
|
}
|
|
|
|
return RecursivelyRewriteEqualsExpression(left, right, pattern);
|
|
}
|
|
private DbExpression RecursivelyRewriteEqualsExpression(DbExpression left, DbExpression right, EqualsPattern pattern)
|
|
{
|
|
// check if either side is an initializer type
|
|
RowType leftType = left.ResultType.EdmType as RowType;
|
|
RowType rightType = left.ResultType.EdmType as RowType;
|
|
|
|
if (null != leftType || null != rightType)
|
|
{
|
|
if ((null != leftType && null != rightType) && leftType.EdmEquals(rightType))
|
|
{
|
|
DbExpression shreddedEquals = null;
|
|
// if the types are the same, use struct equivalence semantics
|
|
foreach (EdmProperty property in leftType.Properties)
|
|
{
|
|
DbPropertyExpression leftElement = left.Property(property);
|
|
DbPropertyExpression rightElement = right.Property(property);
|
|
DbExpression elementsEquals = RecursivelyRewriteEqualsExpression(
|
|
leftElement, rightElement, pattern);
|
|
|
|
// build up and expression
|
|
if (null == shreddedEquals) { shreddedEquals = elementsEquals; }
|
|
else { shreddedEquals = shreddedEquals.And(elementsEquals); }
|
|
}
|
|
return shreddedEquals;
|
|
}
|
|
else
|
|
{
|
|
// if one or both sides is an initializer and the types are not the same,
|
|
// "equals" always evaluates to false
|
|
return DbExpressionBuilder.False;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
return ImplementEquality(left, right, pattern);
|
|
}
|
|
}
|
|
|
|
// For comparisons, where the left and right side are nullable or not nullable,
|
|
// here are the (compositionally safe) null equality predicates:
|
|
// -- x NOT NULL, y NULL
|
|
// x = y AND NOT (y IS NULL)
|
|
// -- x NULL, y NULL
|
|
// (x = y AND (NOT (x IS NULL OR y IS NULL))) OR (x IS NULL AND y IS NULL)
|
|
// -- x NOT NULL, y NOT NULL
|
|
// x = y
|
|
// -- x NULL, y NOT NULL
|
|
// x = y AND NOT (x IS NULL)
|
|
private DbExpression ImplementEquality(DbExpression left, DbExpression right, EqualsPattern pattern)
|
|
{
|
|
switch (left.ExpressionKind)
|
|
{
|
|
case DbExpressionKind.Constant:
|
|
switch (right.ExpressionKind)
|
|
{
|
|
case DbExpressionKind.Constant: // constant EQ constant
|
|
return left.Equal(right);
|
|
case DbExpressionKind.Null: // null EQ constant --> false
|
|
return DbExpressionBuilder.False;
|
|
default:
|
|
return ImplementEqualityConstantAndUnknown((System.Data.Common.CommandTrees.DbConstantExpression)left, right, pattern);
|
|
}
|
|
case DbExpressionKind.Null:
|
|
switch (right.ExpressionKind)
|
|
{
|
|
case DbExpressionKind.Constant: // null EQ constant --> false
|
|
return DbExpressionBuilder.False;
|
|
case DbExpressionKind.Null: // null EQ null --> true
|
|
return DbExpressionBuilder.True;
|
|
default: // null EQ right --> right IS NULL
|
|
return right.IsNull();
|
|
}
|
|
default: // unknown
|
|
switch (right.ExpressionKind)
|
|
{
|
|
case DbExpressionKind.Constant:
|
|
return ImplementEqualityConstantAndUnknown((System.Data.Common.CommandTrees.DbConstantExpression)right, left, pattern);
|
|
case DbExpressionKind.Null: // left EQ null --> left IS NULL
|
|
return left.IsNull();
|
|
default:
|
|
return ImplementEqualityUnknownArguments(left, right, pattern);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Generate an equality expression with one unknown operator and
|
|
private DbExpression ImplementEqualityConstantAndUnknown(
|
|
System.Data.Common.CommandTrees.DbConstantExpression constant, DbExpression unknown, EqualsPattern pattern)
|
|
{
|
|
switch (pattern)
|
|
{
|
|
case EqualsPattern.Store:
|
|
case EqualsPattern.PositiveNullEqualityNonComposable: // for Joins
|
|
return constant.Equal(unknown); // either both are non-null, or one is null and the predicate result is undefined
|
|
case EqualsPattern.PositiveNullEqualityComposable:
|
|
if (!_funcletizer.RootContext.ContextOptions.UseCSharpNullComparisonBehavior)
|
|
{
|
|
return constant.Equal(unknown); // same as EqualsPattern.PositiveNullEqualityNonComposable
|
|
}
|
|
return constant.Equal(unknown).And(unknown.IsNull().Not()); // add more logic to avoid undefined result for true clr semantics
|
|
default:
|
|
Debug.Fail("unknown pattern");
|
|
return null;
|
|
}
|
|
}
|
|
|
|
// Generate an equality expression where the values of the left and right operands are completely unknown
|
|
private DbExpression ImplementEqualityUnknownArguments(DbExpression left, DbExpression right, EqualsPattern pattern)
|
|
{
|
|
switch (pattern)
|
|
{
|
|
case EqualsPattern.Store: // left EQ right
|
|
return left.Equal(right);
|
|
case EqualsPattern.PositiveNullEqualityNonComposable: // for Joins
|
|
return left.Equal(right).Or(left.IsNull().And(right.IsNull()));
|
|
case EqualsPattern.PositiveNullEqualityComposable:
|
|
{
|
|
var bothNotNull = left.Equal(right);
|
|
var bothNull = left.IsNull().And(right.IsNull());
|
|
if (!_funcletizer.RootContext.ContextOptions.UseCSharpNullComparisonBehavior)
|
|
{
|
|
return bothNotNull.Or(bothNull); // same as EqualsPattern.PositiveNullEqualityNonComposable
|
|
}
|
|
// add more logic to avoid undefined result for true clr semantics, ensuring composability
|
|
// (left EQ right AND NOT (left IS NULL OR right IS NULL)) OR (left IS NULL AND right IS NULL)
|
|
var anyOneIsNull = left.IsNull().Or(right.IsNull());
|
|
return (bothNotNull.And(anyOneIsNull.Not())).Or(bothNull);
|
|
}
|
|
default:
|
|
Debug.Fail("unexpected pattern");
|
|
return null;
|
|
}
|
|
}
|
|
|
|
#endregion
|
|
|
|
#region Helper Methods Shared by Translators
|
|
/// <summary>
|
|
/// Helper method for String.StartsWith, String.EndsWith and String.Contains
|
|
///
|
|
/// object.Method(argument), where Method is one of String.StartsWith, String.EndsWith or
|
|
/// String.Contains is translated into:
|
|
/// 1) If argument is a constant or parameter and the provider supports escaping:
|
|
/// object like ("%") + argument1 + ("%"), where argument1 is argument escaped by the provider
|
|
/// and ("%") are appended on the begining/end depending on whether
|
|
/// insertPercentAtStart/insertPercentAtEnd are specified
|
|
/// 2) Otherwise:
|
|
/// object.Method(argument) -> defaultTranslator
|
|
/// </summary>
|
|
/// <param name="call"></param>
|
|
/// <param name="insertPercentAtStart">Should '%' be inserted at the begining of the pattern</param>
|
|
/// <param name="insertPercentAtEnd">Should '%' be inserted at the end of the pattern</param>
|
|
/// <param name="defaultTranslator">The delegate that provides the default translation</param>
|
|
/// <returns>The translation</returns>
|
|
private DbExpression TranslateFunctionIntoLike(MethodCallExpression call, bool insertPercentAtStart, bool insertPercentAtEnd, Func<ExpressionConverter, MethodCallExpression, DbExpression, DbExpression, DbExpression> defaultTranslator)
|
|
{
|
|
char escapeChar;
|
|
bool providerSupportsEscapingLikeArgument = this.ProviderManifest.SupportsEscapingLikeArgument(out escapeChar);
|
|
bool useLikeTranslation = false;
|
|
bool specifyEscape = true;
|
|
|
|
Expression patternExpression = call.Arguments[0];
|
|
Expression inputExpression = call.Object;
|
|
|
|
QueryParameterExpression queryParameterExpression = patternExpression as QueryParameterExpression;
|
|
if (providerSupportsEscapingLikeArgument && (queryParameterExpression != null))
|
|
{
|
|
useLikeTranslation = true;
|
|
bool specifyEscapeDummy;
|
|
patternExpression = queryParameterExpression.EscapeParameterForLike(input => PreparePattern(input, insertPercentAtStart, insertPercentAtEnd, out specifyEscapeDummy));
|
|
}
|
|
|
|
DbExpression translatedPatternExpression = this.TranslateExpression(patternExpression);
|
|
DbExpression translatedInputExpression = this.TranslateExpression(inputExpression);
|
|
|
|
if (providerSupportsEscapingLikeArgument && translatedPatternExpression.ExpressionKind == DbExpressionKind.Constant)
|
|
{
|
|
useLikeTranslation = true;
|
|
DbConstantExpression constantExpression = (DbConstantExpression)translatedPatternExpression;
|
|
|
|
string preparedValue = PreparePattern((string)constantExpression.Value, insertPercentAtStart, insertPercentAtEnd, out specifyEscape);
|
|
Debug.Assert(preparedValue != null, "The prepared value should not be null when the input is non-null");
|
|
|
|
//Note: the result type needs to be taken from the original expression, as the user may have specified Unicode/Non-Unicode
|
|
translatedPatternExpression = DbExpressionBuilder.Constant(constantExpression.ResultType, preparedValue);
|
|
}
|
|
|
|
DbExpression result;
|
|
if (useLikeTranslation)
|
|
{
|
|
if (specifyEscape)
|
|
{
|
|
//DevDiv #326720: The constant expression for the escape character should not have unicode set by default
|
|
var escapeExpression = DbExpressionBuilder.Constant(EdmProviderManifest.Instance.GetCanonicalModelTypeUsage(PrimitiveTypeKind.String), new String(new char[] { escapeChar }));
|
|
result = DbExpressionBuilder.Like(translatedInputExpression, translatedPatternExpression, escapeExpression);
|
|
}
|
|
else
|
|
{
|
|
result = DbExpressionBuilder.Like(translatedInputExpression, translatedPatternExpression);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
result = defaultTranslator(this, call, translatedPatternExpression, translatedInputExpression);
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Prepare the given input patternValue into a pattern to be used in a LIKE expression by
|
|
/// first escaping it by the provider and then appending "%" and the beginging/end depending
|
|
/// on whether insertPercentAtStart/insertPercentAtEnd is specified.
|
|
/// </summary>
|
|
private string PreparePattern(string patternValue, bool insertPercentAtStart, bool insertPercentAtEnd, out bool specifyEscape)
|
|
{
|
|
// Dev10 #800466: The pattern value if originating from a parameter value could be null
|
|
if (patternValue == null)
|
|
{
|
|
specifyEscape = false;
|
|
return null;
|
|
}
|
|
|
|
string escapedPatternValue = this.ProviderManifest.EscapeLikeArgument(patternValue);
|
|
|
|
if (escapedPatternValue == null)
|
|
{
|
|
throw EntityUtil.ProviderIncompatible(System.Data.Entity.Strings.ProviderEscapeLikeArgumentReturnedNull);
|
|
}
|
|
|
|
specifyEscape = patternValue != escapedPatternValue;
|
|
|
|
System.Text.StringBuilder patternBuilder = new System.Text.StringBuilder();
|
|
if (insertPercentAtStart)
|
|
{
|
|
patternBuilder.Append("%");
|
|
}
|
|
patternBuilder.Append(escapedPatternValue);
|
|
if (insertPercentAtEnd)
|
|
{
|
|
patternBuilder.Append("%");
|
|
}
|
|
|
|
return patternBuilder.ToString();
|
|
}
|
|
|
|
/// <summary>
|
|
/// Translates the arguments into DbExpressions
|
|
/// and creates a canonical function with the given functionName and these arguments
|
|
/// </summary>
|
|
/// <param name="functionName">Should represent a non-aggregate canonical function</param>
|
|
/// <param name="Expression">Passed only for error handling purposes</param>
|
|
/// <param name="linqArguments"></param>
|
|
/// <returns></returns>
|
|
private DbFunctionExpression TranslateIntoCanonicalFunction(string functionName, Expression Expression, params Expression[] linqArguments)
|
|
{
|
|
DbExpression[] translatedArguments = new DbExpression[linqArguments.Length];
|
|
for (int i = 0; i < linqArguments.Length; i++)
|
|
{
|
|
translatedArguments[i] = TranslateExpression(linqArguments[i]);
|
|
}
|
|
return CreateCanonicalFunction(functionName, Expression, translatedArguments);
|
|
}
|
|
|
|
/// <summary>
|
|
/// Creates a canonical function with the given name and the given arguments
|
|
/// </summary>
|
|
/// <param name="functionName">Should represent a non-aggregate canonical function</param>
|
|
/// <param name="Expression">Passed only for error handling purposes</param>
|
|
/// <param name="translatedArguments"></param>
|
|
/// <returns></returns>
|
|
private DbFunctionExpression CreateCanonicalFunction(string functionName, Expression Expression, params DbExpression[] translatedArguments)
|
|
{
|
|
List<TypeUsage> translatedArgumentTypes = new List<TypeUsage>(translatedArguments.Length);
|
|
foreach (DbExpression translatedArgument in translatedArguments)
|
|
{
|
|
translatedArgumentTypes.Add(translatedArgument.ResultType);
|
|
}
|
|
EdmFunction function = FindCanonicalFunction(functionName, translatedArgumentTypes, false /* isGroupAggregateFunction */, Expression);
|
|
return function.Invoke(translatedArguments);
|
|
}
|
|
|
|
/// <summary>
|
|
/// Finds a canonical function with the given functionName and argumentTypes
|
|
/// </summary>
|
|
/// <param name="functionName"></param>
|
|
/// <param name="argumentTypes"></param>
|
|
/// <param name="isGroupAggregateFunction"></param>
|
|
/// <param name="Expression"></param>
|
|
/// <returns></returns>
|
|
private EdmFunction FindCanonicalFunction(string functionName, IList<TypeUsage> argumentTypes, bool isGroupAggregateFunction, Expression Expression)
|
|
{
|
|
return FindFunction(EdmNamespaceName, functionName, argumentTypes, isGroupAggregateFunction, Expression);
|
|
}
|
|
|
|
/// <summary>
|
|
/// Finds a function with the given namespaceName, functionName and argumentTypes
|
|
/// </summary>
|
|
/// <param name="namespaceName"></param>
|
|
/// <param name="functionName"></param>
|
|
/// <param name="argumentTypes"></param>
|
|
/// <param name="isGroupAggregateFunction"></param>
|
|
/// <param name="Expression"></param>
|
|
/// <returns></returns>
|
|
private EdmFunction FindFunction(string namespaceName, string functionName, IList<TypeUsage> argumentTypes, bool isGroupAggregateFunction, Expression Expression)
|
|
{
|
|
// find the function
|
|
IList<EdmFunction> candidateFunctions;
|
|
if (!_perspective.TryGetFunctionByName(namespaceName, functionName, false /* ignore case */, out candidateFunctions))
|
|
{
|
|
ThrowUnresolvableFunction(Expression);
|
|
}
|
|
|
|
Debug.Assert(null != candidateFunctions && candidateFunctions.Count > 0, "provider functions must not be null or empty");
|
|
|
|
bool isAmbiguous;
|
|
EdmFunction function = FunctionOverloadResolver.ResolveFunctionOverloads(candidateFunctions, argumentTypes, isGroupAggregateFunction, out isAmbiguous);
|
|
if (isAmbiguous || null == function)
|
|
{
|
|
ThrowUnresolvableFunctionOverload(Expression, isAmbiguous);
|
|
}
|
|
return function;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Helper method for FindFunction
|
|
/// </summary>
|
|
/// <param name="Expression"></param>
|
|
private static void ThrowUnresolvableFunction(Expression Expression)
|
|
{
|
|
if (Expression.NodeType == ExpressionType.Call)
|
|
{
|
|
MethodInfo methodInfo = ((MethodCallExpression)Expression).Method;
|
|
throw EntityUtil.NotSupported(System.Data.Entity.Strings.ELinq_UnresolvableFunctionForMethod(methodInfo, methodInfo.DeclaringType));
|
|
}
|
|
else if (Expression.NodeType == ExpressionType.MemberAccess)
|
|
{
|
|
string memberName;
|
|
Type memberType;
|
|
MemberInfo memberInfo = TypeSystem.PropertyOrField(((MemberExpression)Expression).Member, out memberName, out memberType);
|
|
throw EntityUtil.NotSupported(System.Data.Entity.Strings.ELinq_UnresolvableFunctionForMember(memberInfo, memberInfo.DeclaringType));
|
|
}
|
|
throw EntityUtil.NotSupported(System.Data.Entity.Strings.ELinq_UnresolvableFunctionForExpression(Expression.NodeType));
|
|
}
|
|
|
|
/// <summary>
|
|
/// Helper method for FindCanonicalFunction
|
|
/// </summary>
|
|
/// <param name="Expression"></param>
|
|
private static void ThrowUnresolvableFunctionOverload(Expression Expression, bool isAmbiguous)
|
|
{
|
|
if (Expression.NodeType == ExpressionType.Call)
|
|
{
|
|
MethodInfo methodInfo = ((MethodCallExpression)Expression).Method;
|
|
if (isAmbiguous)
|
|
{
|
|
throw EntityUtil.NotSupported(System.Data.Entity.Strings.ELinq_UnresolvableFunctionForMethodAmbiguousMatch(methodInfo, methodInfo.DeclaringType));
|
|
}
|
|
else
|
|
{
|
|
throw EntityUtil.NotSupported(System.Data.Entity.Strings.ELinq_UnresolvableFunctionForMethodNotFound(methodInfo, methodInfo.DeclaringType));
|
|
}
|
|
}
|
|
else if (Expression.NodeType == ExpressionType.MemberAccess)
|
|
{
|
|
string memberName;
|
|
Type memberType;
|
|
MemberInfo memberInfo = TypeSystem.PropertyOrField(((MemberExpression)Expression).Member, out memberName, out memberType);
|
|
throw EntityUtil.NotSupported(System.Data.Entity.Strings.ELinq_UnresolvableStoreFunctionForMember(memberInfo, memberInfo.DeclaringType));
|
|
}
|
|
throw EntityUtil.NotSupported(System.Data.Entity.Strings.ELinq_UnresolvableStoreFunctionForExpression(Expression.NodeType));
|
|
}
|
|
|
|
private DbNewInstanceExpression CreateNewRowExpression(List<KeyValuePair<string, DbExpression>> columns, InitializerMetadata initializerMetadata)
|
|
{
|
|
List<DbExpression> propertyValues = new List<DbExpression>(columns.Count);
|
|
List<EdmProperty> properties = new List<EdmProperty>(columns.Count);
|
|
for (int i = 0; i < columns.Count; i++)
|
|
{
|
|
var column = columns[i];
|
|
propertyValues.Add(column.Value);
|
|
properties.Add(new EdmProperty(column.Key, column.Value.ResultType));
|
|
}
|
|
RowType rowType = new RowType(properties, initializerMetadata);
|
|
TypeUsage typeUsage = TypeUsage.Create(rowType);
|
|
return typeUsage.New(propertyValues);
|
|
}
|
|
|
|
#endregion
|
|
|
|
#region Private enums
|
|
// Describes different implementation pattern for equality comparisons.
|
|
// For all patterns, if one side of the expression is a constant null, converts to an IS NULL
|
|
// expression (or resolves to 'true' or 'false' if some constraint is known for the other side).
|
|
//
|
|
// If neither side is a constant null, the semantics differ:
|
|
//
|
|
// (1) (left EQ right) => left and right are equal and not null, so return true.
|
|
// (2) (left IS NULL AND right IS NULL) => Both left and right are null, so return true.
|
|
// (3) NOT (left IS NULL OR right IS NULL) =>
|
|
// If only one of left or right is null, (1) evaluates to "unknown" and (2) evaluates to false. So we get "unknown" from DB which is null in C#.
|
|
// This is not desired as it does not help in composability. Hence, (3) is used to return false instead of "unknown" when only one of the operands is null.
|
|
//
|
|
// Store: (1)
|
|
// PositiveNullEqualityNonComposable: (1) OR (2) - suitable only for Join operators, as they are not composable
|
|
// PositiveNullEqualityComposable: (1) OR (2) AND (3)
|
|
//
|
|
// In the actual implementation (see ImplementEquality), optimizations exist if one or the other
|
|
// side is known not to be null.
|
|
private enum EqualsPattern
|
|
{
|
|
Store, // defer to store
|
|
PositiveNullEqualityNonComposable, // simulate C# semantics in store, return "null" if left or right is null, but not both. Suitable for joins.
|
|
PositiveNullEqualityComposable, // simulate C# semantics in store, always return true or false
|
|
}
|
|
#endregion
|
|
}
|
|
}
|