|
//---------------------------------------------------------------------
// <copyright file="GeneratedView.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
//
// @owner Microsoft
// @backupOwner Microsoft
//---------------------------------------------------------------------
namespace System.Data.Mapping.ViewGeneration
{
using System.Collections.Generic;
using System.Data.Common.CommandTrees;
using System.Data.Common.CommandTrees.Internal;
using System.Data.Common.EntitySql;
using System.Data.Common.Utils;
using System.Data.Entity.Util;
using System.Data.Mapping.ViewGeneration.Utils;
using System.Data.Metadata.Edm;
using System.Data.Query.InternalTrees;
using System.Data.Query.PlanCompiler;
using System.Diagnostics;
using System.Text;
/// <summary>
/// Holds the view generated for a given OFTYPE(Extent, Type) combination.
/// </summary>
internal sealed class GeneratedView : InternalBase
{
#region Factory
/// <summary>
/// Creates generated view object for the combination of the <paramref name="extent"/> and the <paramref name="type"/>.
/// This constructor is used for regular cell-based view generation.
/// </summary>
internal static GeneratedView CreateGeneratedView(EntitySetBase extent,
EdmType type,
DbQueryCommandTree commandTree,
string eSQL,
StorageMappingItemCollection mappingItemCollection,
ConfigViewGenerator config)
{
// If config.GenerateEsql is specified, eSQL must be non-null.
// If config.GenerateEsql is false, commandTree is non-null except the case when loading pre-compiled eSQL views.
Debug.Assert(!config.GenerateEsql || !String.IsNullOrEmpty(eSQL), "eSQL must be specified");
DiscriminatorMap discriminatorMap = null;
if (commandTree != null)
{
commandTree = ViewSimplifier.SimplifyView(extent, commandTree);
// See if the view matches the "discriminated" pattern (allows simplification of generated store commands)
if (extent.BuiltInTypeKind == BuiltInTypeKind.EntitySet)
{
if (DiscriminatorMap.TryCreateDiscriminatorMap((EntitySet)extent, commandTree.Query, out discriminatorMap))
{
Debug.Assert(discriminatorMap != null, "discriminatorMap == null after it has been created");
}
}
}
return new GeneratedView(extent, type, commandTree, eSQL, discriminatorMap, mappingItemCollection, config);
}
/// <summary>
/// Creates generated view object for the combination of the <paramref name="extent"/> and the <paramref name="type"/>.
/// This constructor is used for FK association sets only.
/// </summary>
internal static GeneratedView CreateGeneratedViewForFKAssociationSet(EntitySetBase extent,
EdmType type,
DbQueryCommandTree commandTree,
StorageMappingItemCollection mappingItemCollection,
ConfigViewGenerator config)
{
return new GeneratedView(extent, type, commandTree, null, null, mappingItemCollection, config);
}
/// <summary>
/// Creates generated view object for the combination of the <paramref name="setMapping"/>.Set and the <paramref name="type"/>.
/// This constructor is used for user-defined query views only.
/// </summary>
internal static bool TryParseUserSpecifiedView(StorageSetMapping setMapping,
EntityTypeBase type,
string eSQL,
bool includeSubtypes,
StorageMappingItemCollection mappingItemCollection,
ConfigViewGenerator config,
/*out*/ IList<EdmSchemaError> errors,
out GeneratedView generatedView)
{
bool failed = false;
DbQueryCommandTree commandTree;
DiscriminatorMap discriminatorMap;
Exception parserException;
if (!GeneratedView.TryParseView(eSQL, true, setMapping.Set, mappingItemCollection, config, out commandTree, out discriminatorMap, out parserException))
{
EdmSchemaError error = new EdmSchemaError(System.Data.Entity.Strings.Mapping_Invalid_QueryView2(setMapping.Set.Name, parserException.Message),
(int)StorageMappingErrorCode.InvalidQueryView, EdmSchemaErrorSeverity.Error,
setMapping.EntityContainerMapping.SourceLocation, setMapping.StartLineNumber, setMapping.StartLinePosition, parserException);
errors.Add(error);
failed = true;
}
else
{
Debug.Assert(commandTree != null, "commandTree not set after parsing the view");
// Verify that all expressions appearing in the view are supported.
foreach (var error in ViewValidator.ValidateQueryView(commandTree, setMapping, type, includeSubtypes))
{
errors.Add(error);
failed = true;
}
// Verify that the result type of the query view is assignable to the element type of the entityset
CollectionType queryResultType = (commandTree.Query.ResultType.EdmType) as CollectionType;
if ((queryResultType == null) || (!setMapping.Set.ElementType.IsAssignableFrom(queryResultType.TypeUsage.EdmType)))
{
EdmSchemaError error = new EdmSchemaError(System.Data.Entity.Strings.Mapping_Invalid_QueryView_Type(setMapping.Set.Name),
(int)StorageMappingErrorCode.InvalidQueryViewResultType, EdmSchemaErrorSeverity.Error,
setMapping.EntityContainerMapping.SourceLocation, setMapping.StartLineNumber, setMapping.StartLinePosition);
errors.Add(error);
failed = true;
}
}
if (!failed)
{
generatedView = new GeneratedView(setMapping.Set, type, commandTree, eSQL, discriminatorMap, mappingItemCollection, config);
return true;
}
else
{
generatedView = null;
return false;
}
}
private GeneratedView(EntitySetBase extent,
EdmType type,
DbQueryCommandTree commandTree,
string eSQL,
DiscriminatorMap discriminatorMap,
StorageMappingItemCollection mappingItemCollection,
ConfigViewGenerator config)
{
// At least one of the commandTree or eSQL must be specified.
// Both are specified in the case of user-defined views.
Debug.Assert(commandTree != null || !String.IsNullOrEmpty(eSQL), "commandTree or eSQL must be specified");
m_extent = extent;
m_type = type;
m_commandTree = commandTree;
m_eSQL = eSQL;
m_discriminatorMap = discriminatorMap;
m_mappingItemCollection = mappingItemCollection;
m_config = config;
if (m_config.IsViewTracing)
{
StringBuilder trace = new StringBuilder(1024);
this.ToCompactString(trace);
Helpers.FormatTraceLine("CQL view for {0}", trace.ToString());
}
}
#endregion
#region Fields
private readonly EntitySetBase m_extent;
private readonly EdmType m_type;
private DbQueryCommandTree m_commandTree; //We cache CQTs for Update Views sicne that is the one update stack works of.
private readonly string m_eSQL;
private Node m_internalTreeNode; //we cache IQTs for Query Views since that is the one query stack works of.
private DiscriminatorMap m_discriminatorMap;
private readonly StorageMappingItemCollection m_mappingItemCollection;
private readonly ConfigViewGenerator m_config;
#endregion
#region Properties
internal string eSQL
{
get { return m_eSQL; }
}
#endregion
#region Methods
internal DbQueryCommandTree GetCommandTree()
{
if (m_commandTree == null)
{
Debug.Assert(!String.IsNullOrEmpty(m_eSQL), "m_eSQL must be initialized");
Exception parserException;
if (TryParseView(m_eSQL, false, m_extent, m_mappingItemCollection, m_config, out m_commandTree, out m_discriminatorMap, out parserException))
{
Debug.Assert(m_commandTree != null, "m_commandTree not set after parsing the view");
return m_commandTree;
}
else
{
throw new MappingException(System.Data.Entity.Strings.Mapping_Invalid_QueryView(m_extent.Name, parserException.Message));
}
}
return m_commandTree;
}
internal Node GetInternalTree(Command targetIqtCommand)
{
Debug.Assert(m_extent.EntityContainer.DataSpace == DataSpace.CSpace, "Internal Tree should be asked only for query view");
if (m_internalTreeNode == null)
{
DbQueryCommandTree tree = GetCommandTree();
// Convert this into an ITree first
Command itree = ITreeGenerator.Generate(tree, m_discriminatorMap);
// Pull out the root physical project-op, and copy this itree into our own itree
PlanCompiler.Assert(itree.Root.Op.OpType == OpType.PhysicalProject,
"Expected a physical projectOp at the root of the tree - found " + itree.Root.Op.OpType);
// #554756: VarVec enumerators are not cached on the shared Command instance.
itree.DisableVarVecEnumCaching();
m_internalTreeNode = itree.Root.Child0;
}
Debug.Assert(m_internalTreeNode != null, "m_internalTreeNode != null");
return OpCopier.Copy(targetIqtCommand, m_internalTreeNode);
}
/// <summary>
/// Given an extent and its corresponding view, invokes the parser to check if the view definition is syntactically correct.
/// Iff parsing succeeds: <paramref name="commandTree"/> and <paramref name="discriminatorMap"/> are set to the parse result and method returns true,
/// otherwise if parser has thrown a catchable exception, it is returned via <paramref name="parserException"/> parameter,
/// otherwise exception is re-thrown.
/// </summary>
private static bool TryParseView(string eSQL,
bool isUserSpecified,
EntitySetBase extent,
StorageMappingItemCollection mappingItemCollection,
ConfigViewGenerator config,
out DbQueryCommandTree commandTree,
out DiscriminatorMap discriminatorMap,
out Exception parserException)
{
commandTree = null;
discriminatorMap = null;
parserException = null;
// We do not catch any internal exceptions any more
config.StartSingleWatch(PerfType.ViewParsing);
try
{
// If it is a user specified view, allow all queries. Otherwise parse the view in the restricted mode.
ParserOptions.CompilationMode compilationMode = ParserOptions.CompilationMode.RestrictedViewGenerationMode;
if (isUserSpecified)
{
compilationMode = ParserOptions.CompilationMode.UserViewGenerationMode;
}
Debug.Assert(!String.IsNullOrEmpty(eSQL), "eSQL query is not specified");
commandTree = (DbQueryCommandTree)ExternalCalls.CompileView(eSQL, mappingItemCollection, compilationMode);
if (!isUserSpecified || AppSettings.SimplifyUserSpecifiedViews)
{
commandTree = ViewSimplifier.SimplifyView(extent, commandTree);
}
// See if the view matches the "discriminated" pattern (allows simplification of generated store commands)
if (extent.BuiltInTypeKind == BuiltInTypeKind.EntitySet)
{
if (DiscriminatorMap.TryCreateDiscriminatorMap((EntitySet)extent, commandTree.Query, out discriminatorMap))
{
Debug.Assert(discriminatorMap != null, "discriminatorMap == null after it has been created");
}
}
}
catch (Exception e)
{
// Catching all the exception types since Query parser seems to be throwing veriety of
// exceptions - EntityException, ArgumentException, ArgumentNullException etc.
if (EntityUtil.IsCatchableExceptionType(e))
{
parserException = e;
}
else
{
throw;
}
}
finally
{
config.StopSingleWatch(PerfType.ViewParsing);
}
Debug.Assert(commandTree != null || parserException != null, "Either commandTree or parserException is expected.");
// Note: m_commandTree might have been initialized by a previous call to this method, so in consequent calls it might occur that
// both m_commandTree and parserException are not null - this would mean that the last parse attempt failed, but m_commandTree value is
// preserved from the previous call.
return parserException == null;
}
#endregion
#region String Methods
internal override void ToCompactString(StringBuilder builder)
{
bool ofTypeView = m_type != m_extent.ElementType;
if (ofTypeView)
{
builder.Append("OFTYPE(");
}
builder.AppendFormat("{0}.{1}", m_extent.EntityContainer.Name, m_extent.Name);
if (ofTypeView)
{
builder.Append(", ").Append(m_type.Name).Append(')');
}
builder.AppendLine(" = ");
if (!String.IsNullOrEmpty(m_eSQL))
{
builder.Append(m_eSQL);
}
else
{
builder.Append(m_commandTree.Print());
}
}
#endregion
}
}
|