private DbQueryCommandTree Simplify(DbQueryCommandTree view)
{
DbExpression query = PatternMatchRuleProcessor.Create(PatternMatchRule.Create(ViewSimplifier._patternCollapseNestedProjection, new Func <DbExpression, DbExpression>(ViewSimplifier.CollapseNestedProjection)), PatternMatchRule.Create(ViewSimplifier._patternCase, new Func <DbExpression, DbExpression>(ViewSimplifier.SimplifyCaseStatement)), PatternMatchRule.Create(ViewSimplifier._patternNestedTphDiscriminator, new Func <DbExpression, DbExpression>(ViewSimplifier.SimplifyNestedTphDiscriminator)), PatternMatchRule.Create(ViewSimplifier._patternEntityConstructor, new Func <DbExpression, DbExpression>(this.AddFkRelatedEntityRefs)))(view.Query);
view = DbQueryCommandTree.FromValidExpression(view.MetadataWorkspace, view.DataSpace, query, view.UseDatabaseNullSemantics);
return(view);
}
internal DbQueryCommandTree GenerateFunctionView(out DiscriminatorMap discriminatorMap)
{
DebugCheck.NotNull(m_mappingItemCollection);
discriminatorMap = null;
// Prepare the direct call of the store function as StoreFunction(@EdmFunc_p1, ..., @EdmFunc_pN).
// Note that function call arguments are command parameters created from the m_edmFunction parameters.
Debug.Assert(TargetFunction != null, "this.TargetFunction != null");
DbExpression storeFunctionInvoke = TargetFunction.Invoke(GetParametersForTargetFunctionCall());
// Generate the query expression producing c-space result from s-space function call(s).
DbExpression queryExpression;
if (m_structuralTypeMappings != null)
{
queryExpression = GenerateStructuralTypeResultMappingView(storeFunctionInvoke, out discriminatorMap);
Debug.Assert(
queryExpression != null &&
TypeSemantics.IsPromotableTo(queryExpression.ResultType, FunctionImport.ReturnParameter.TypeUsage),
"TypeSemantics.IsPromotableTo(queryExpression.ResultType, this.FunctionImport.ReturnParameter.TypeUsage)");
}
else
{
queryExpression = GenerateScalarResultMappingView(storeFunctionInvoke);
Debug.Assert(
queryExpression != null &&
TypeSemantics.IsEqual(queryExpression.ResultType, FunctionImport.ReturnParameter.TypeUsage),
"TypeSemantics.IsEqual(queryExpression.ResultType, this.FunctionImport.ReturnParameter.TypeUsage)");
}
// Generate parameterized command, where command parameters are semantically the c-space function parameters.
return(DbQueryCommandTree.FromValidExpression(
m_mappingItemCollection.Workspace, TargetPerspective.TargetPerspectiveDataSpace, queryExpression));
}
public virtual ObjectQueryExecutionPlan Prepare(
ObjectContext context, DbQueryCommandTree tree, Type elementType, MergeOption mergeOption, Span span,
IEnumerable <Tuple <ObjectParameter, QueryParameterExpression> > compiledQueryParameters, AliasGenerator aliasGenerator)
{
var treeResultType = tree.Query.ResultType;
// Rewrite this tree for Span?
DbExpression spannedQuery = null;
SpanIndex spanInfo;
if (ObjectSpanRewriter.TryRewrite(tree, span, mergeOption, aliasGenerator, out spannedQuery, out spanInfo))
{
tree = DbQueryCommandTree.FromValidExpression(tree.MetadataWorkspace, tree.DataSpace, spannedQuery);
}
else
{
spanInfo = null;
}
var entityDefinition = CreateCommandDefinition(context, tree);
var cacheManager = context.Perspective.MetadataWorkspace.GetQueryCacheManager();
var shaperFactory = Translator.TranslateColumnMap(
_translator,
elementType, cacheManager, entityDefinition.CreateColumnMap(null),
context.MetadataWorkspace, spanInfo, mergeOption, false);
// attempt to determine entity information for this query (e.g. which entity type and which entity set)
EntitySet singleEntitySet = null;
// determine if the entity set is unambiguous given the entity type
if (treeResultType.EdmType.BuiltInTypeKind == BuiltInTypeKind.CollectionType &&
entityDefinition.EntitySets != null)
{
foreach (var entitySet in entityDefinition.EntitySets)
{
if (entitySet != null &&
entitySet.ElementType.IsAssignableFrom(((CollectionType)treeResultType.EdmType).TypeUsage.EdmType))
{
if (singleEntitySet == null)
{
// found a single match
singleEntitySet = entitySet;
}
else
{
// there's more than one matching entity set
singleEntitySet = null;
break;
}
}
}
}
return(new ObjectQueryExecutionPlan(
entityDefinition, shaperFactory, treeResultType, mergeOption, singleEntitySet, compiledQueryParameters));
}
/// <summary>
/// The only entry point.
/// Rewrites the given tree by replacing expressions that are not directly supported on SQL Server 2000
/// with alterntive translations.
/// </summary>
/// <param name="originalTree">The tree to rewrite</param>
/// <returns>The new tree</returns>
internal static DbQueryCommandTree Rewrite(DbQueryCommandTree originalTree)
{
Debug.Assert(originalTree != null, "OriginalTree is null");
Sql8ExpressionRewriter rewriter = new Sql8ExpressionRewriter(originalTree.MetadataWorkspace);
DbExpression newQuery = rewriter.VisitExpression(originalTree.Query);
return(DbQueryCommandTree.FromValidExpression(originalTree.MetadataWorkspace, originalTree.DataSpace, newQuery));
}
internal DbQueryCommandTree GenerateFunctionView(
out DiscriminatorMap discriminatorMap)
{
discriminatorMap = (DiscriminatorMap)null;
DbExpression storeFunctionInvoke = (DbExpression)this.TargetFunction.Invoke(this.GetParametersForTargetFunctionCall());
return(DbQueryCommandTree.FromValidExpression(this._containerMapping.StorageMappingItemCollection.Workspace, DataSpace.SSpace, this.m_structuralTypeMappings == null ? this.GenerateScalarResultMappingView(storeFunctionInvoke) : this.GenerateStructuralTypeResultMappingView(storeFunctionInvoke, out discriminatorMap), true));
}
/// <summary>
/// Returns Cqtl query that represents a query/update mapping view for the view information that was supplied in the constructor.
/// </summary>
internal DbQueryCommandTree GenerateCqt()
{
// Generate a CqlBlock tree and then convert that to CQT.
CqlBlock blockTree = GenerateCqlBlockTree();
DbExpression query = blockTree.AsCqt(true);
Debug.Assert(query != null, "Null CQT generated for query/update view.");
return(DbQueryCommandTree.FromValidExpression(m_mappingItemCollection.Workspace, TargetPerspective.TargetPerspectiveDataSpace, query));
}
// <summary>
// Returns Cqtl query that represents a query/update mapping view for the view information that was supplied in the constructor.
// </summary>
internal DbQueryCommandTree GenerateCqt()
{
// Generate a CqlBlock tree and then convert that to CQT.
var blockTree = GenerateCqlBlockTree();
var query = blockTree.AsCqt(true);
Debug.Assert(query != null, "Null CQT generated for query/update view.");
return(DbQueryCommandTree.FromValidExpression(
m_mappingItemCollection.Workspace, TargetPerspective.TargetPerspectiveDataSpace, query,
useDatabaseNullSemantics: true, disableFilterOverProjectionSimplificationForCustomFunctions: false));
}
public virtual ObjectQueryExecutionPlan Prepare(
ObjectContext context,
DbQueryCommandTree tree,
Type elementType,
MergeOption mergeOption,
bool streaming,
Span span,
IEnumerable <Tuple <ObjectParameter, QueryParameterExpression> > compiledQueryParameters,
AliasGenerator aliasGenerator)
{
TypeUsage resultType = tree.Query.ResultType;
DbExpression newQuery;
SpanIndex spanInfo;
if (ObjectSpanRewriter.TryRewrite(tree, span, mergeOption, aliasGenerator, out newQuery, out spanInfo))
{
tree = DbQueryCommandTree.FromValidExpression(tree.MetadataWorkspace, tree.DataSpace, newQuery, tree.UseDatabaseNullSemantics);
}
else
{
spanInfo = (SpanIndex)null;
}
EntityCommandDefinition commandDefinition = ObjectQueryExecutionPlanFactory.CreateCommandDefinition(context, tree);
ShaperFactory resultShaperFactory = System.Data.Entity.Core.Common.Internal.Materialization.Translator.TranslateColumnMap(this._translator, elementType, commandDefinition.CreateColumnMap((DbDataReader)null), context.MetadataWorkspace, spanInfo, mergeOption, streaming, false);
EntitySet singleEntitySet = (EntitySet)null;
if (resultType.EdmType.BuiltInTypeKind == BuiltInTypeKind.CollectionType && commandDefinition.EntitySets != null)
{
foreach (EntitySet entitySet in commandDefinition.EntitySets)
{
if (entitySet != null && entitySet.ElementType.IsAssignableFrom(((CollectionType)resultType.EdmType).TypeUsage.EdmType))
{
if (singleEntitySet == null)
{
singleEntitySet = entitySet;
}
else
{
singleEntitySet = (EntitySet)null;
break;
}
}
}
}
return(new ObjectQueryExecutionPlan((DbCommandDefinition)commandDefinition, resultShaperFactory, resultType, mergeOption, streaming, singleEntitySet, compiledQueryParameters));
}
private DbQueryCommandTree Simplify(DbQueryCommandTree view)
{
var simplifier = PatternMatchRuleProcessor.Create(
// determines if an expression is of the form outerProject(outerProjection(innerProject(innerNew)))
PatternMatchRule.Create(_patternCollapseNestedProjection, CollapseNestedProjection),
// A case statement can potentially be simplified
PatternMatchRule.Create(_patternCase, SimplifyCaseStatement),
// Nested TPH discriminator pattern can be converted to the expected TPH discriminator pattern
PatternMatchRule.Create(_patternNestedTphDiscriminator, SimplifyNestedTphDiscriminator),
// Entity constructors may be augmented with FK-based related entity refs
PatternMatchRule.Create(_patternEntityConstructor, AddFkRelatedEntityRefs)
);
var queryExpression = view.Query;
queryExpression = simplifier(queryExpression);
view = DbQueryCommandTree.FromValidExpression(view.MetadataWorkspace, view.DataSpace, queryExpression);
return(view);
}
internal override ObjectQueryExecutionPlan GetExecutionPlan(MergeOption?forMergeOption)
{
Debug.Assert(Span == null, "Include span specified on compiled LINQ-based ObjectQuery instead of within the expression tree?");
// If this query has already been prepared, its current execution plan may no longer be valid.
var plan = _cachedPlan;
if (plan != null)
{
// Was a merge option specified in the call to Execute(MergeOption) or set via ObjectQuery.MergeOption?
var explicitMergeOption = GetMergeOption(forMergeOption, UserSpecifiedMergeOption);
// If a merge option was explicitly specified, and it does not match the plan's merge option, then the plan is no longer valid.
// If the context flag UseCSharpNullComparisonBehavior was modified, then the plan is no longer valid.
if ((explicitMergeOption.HasValue &&
explicitMergeOption.Value != plan.MergeOption)
||
_recompileRequired()
||
ObjectContext.ContextOptions.UseCSharpNullComparisonBehavior != _useCSharpNullComparisonBehavior)
{
plan = null;
}
}
// The plan may have been invalidated above, or this query may never have been prepared.
if (plan == null)
{
// Metadata is required to generate the execution plan.
ObjectContext.EnsureMetadata();
// Reset internal state
_recompileRequired = null;
ResetParameters();
// Translate LINQ expression to a DbExpression
var converter = CreateExpressionConverter();
var queryExpression = converter.Convert();
// This delegate tells us when a part of the expression tree has changed requiring a recompile.
_recompileRequired = converter.RecompileRequired;
// Determine the merge option, with the following precedence:
// 1. A merge option was specified explicitly as the argument to Execute(MergeOption).
// 2. The user has set the MergeOption property on the ObjectQuery instance.
// 3. A merge option has been extracted from the 'root' query and propagated to the root of the expression tree.
// 4. The global default merge option.
var mergeOption = EnsureMergeOption(
forMergeOption,
UserSpecifiedMergeOption,
converter.PropagatedMergeOption);
_useCSharpNullComparisonBehavior = ObjectContext.ContextOptions.UseCSharpNullComparisonBehavior;
// If parameters were aggregated from referenced (non-LINQ) ObjectQuery instances then add them to the parameters collection
_linqParameters = converter.GetParameters();
if (_linqParameters != null &&
_linqParameters.Any())
{
var currentParams = EnsureParameters();
currentParams.SetReadOnly(false);
foreach (var pair in _linqParameters)
{
// Note that it is safe to add the parameter directly only
// because parameters are cloned before they are added to the
// converter's parameter collection, or they came from this
// instance's parameter collection in the first place.
var convertedParam = pair.Item1;
currentParams.Add(convertedParam);
}
currentParams.SetReadOnly(true);
}
// Try retrieving the execution plan from the global query cache (if plan caching is enabled).
QueryCacheManager cacheManager = null;
LinqQueryCacheKey cacheKey = null;
if (PlanCachingEnabled && !_recompileRequired())
{
// Create a new cache key that reflects the current state of the Parameters collection
// and the Span object (if any), and uses the specified merge option.
string expressionKey;
if (ExpressionKeyGen.TryGenerateKey(queryExpression, out expressionKey))
{
cacheKey = new LinqQueryCacheKey(
expressionKey,
(null == Parameters ? 0 : Parameters.Count),
(null == Parameters ? null : Parameters.GetCacheKey()),
(null == converter.PropagatedSpan ? null : converter.PropagatedSpan.GetCacheKey()),
mergeOption,
_useCSharpNullComparisonBehavior,
ElementType);
cacheManager = ObjectContext.MetadataWorkspace.GetQueryCacheManager();
ObjectQueryExecutionPlan executionPlan = null;
if (cacheManager.TryCacheLookup(cacheKey, out executionPlan))
{
plan = executionPlan;
}
}
}
// If execution plan wasn't retrieved from the cache, build a new one and cache it.
if (plan == null)
{
var tree = DbQueryCommandTree.FromValidExpression(ObjectContext.MetadataWorkspace, DataSpace.CSpace, queryExpression);
plan = _objectQueryExecutionPlanFactory.Prepare(
ObjectContext, tree, ElementType, mergeOption, converter.PropagatedSpan, null, converter.AliasGenerator);
// If caching is enabled then update the cache now.
// Note: the logic is the same as in EntitySqlQueryState.
if (cacheKey != null)
{
var newEntry = new QueryCacheEntry(cacheKey, plan);
QueryCacheEntry foundEntry = null;
if (cacheManager.TryLookupAndAdd(newEntry, out foundEntry))
{
// If TryLookupAndAdd returns 'true' then the entry was already present in the cache when the attempt to add was made.
// In this case the existing execution plan should be used.
plan = (ObjectQueryExecutionPlan)foundEntry.GetTarget();
}
}
}
// Remember the current plan in the local cache, so that we don't have to recalc the key and look into the global cache
// if the same instance of query gets executed more than once.
_cachedPlan = plan;
}
// Evaluate parameter values for the query.
if (_linqParameters != null)
{
foreach (var pair in _linqParameters)
{
var parameter = pair.Item1;
var parameterExpression = pair.Item2;
if (null != parameterExpression)
{
parameter.Value = parameterExpression.EvaluateParameter(null);
}
}
}
return(plan);
}
internal override ObjectQueryExecutionPlan GetExecutionPlan(
MergeOption?forMergeOption)
{
ObjectQueryExecutionPlan queryExecutionPlan1 = this._cachedPlan;
if (queryExecutionPlan1 != null)
{
MergeOption?mergeOption = ObjectQueryState.GetMergeOption(forMergeOption, this.UserSpecifiedMergeOption);
if (mergeOption.HasValue && mergeOption.Value != queryExecutionPlan1.MergeOption || (this._recompileRequired() || this.ObjectContext.ContextOptions.UseCSharpNullComparisonBehavior != this._useCSharpNullComparisonBehavior))
{
queryExecutionPlan1 = (ObjectQueryExecutionPlan)null;
}
}
if (queryExecutionPlan1 == null)
{
this._recompileRequired = (Func <bool>)null;
this.ResetParameters();
ExpressionConverter expressionConverter = this.CreateExpressionConverter();
DbExpression dbExpression = expressionConverter.Convert();
this._recompileRequired = expressionConverter.RecompileRequired;
MergeOption mergeOption = ObjectQueryState.EnsureMergeOption(forMergeOption, this.UserSpecifiedMergeOption, expressionConverter.PropagatedMergeOption);
this._useCSharpNullComparisonBehavior = this.ObjectContext.ContextOptions.UseCSharpNullComparisonBehavior;
this._linqParameters = expressionConverter.GetParameters();
if (this._linqParameters != null && this._linqParameters.Any <Tuple <ObjectParameter, QueryParameterExpression> >())
{
ObjectParameterCollection parameterCollection = this.EnsureParameters();
parameterCollection.SetReadOnly(false);
foreach (Tuple <ObjectParameter, QueryParameterExpression> linqParameter in this._linqParameters)
{
ObjectParameter objectParameter = linqParameter.Item1;
parameterCollection.Add(objectParameter);
}
parameterCollection.SetReadOnly(true);
}
QueryCacheManager queryCacheManager = (QueryCacheManager)null;
LinqQueryCacheKey key1 = (LinqQueryCacheKey)null;
string key2;
if (this.PlanCachingEnabled && !this._recompileRequired() && ExpressionKeyGen.TryGenerateKey(dbExpression, out key2))
{
key1 = new LinqQueryCacheKey(key2, this.Parameters == null ? 0 : this.Parameters.Count, this.Parameters == null ? (string)null : this.Parameters.GetCacheKey(), expressionConverter.PropagatedSpan == null ? (string)null : expressionConverter.PropagatedSpan.GetCacheKey(), mergeOption, this.EffectiveStreamingBehavior, this._useCSharpNullComparisonBehavior, this.ElementType);
queryCacheManager = this.ObjectContext.MetadataWorkspace.GetQueryCacheManager();
ObjectQueryExecutionPlan queryExecutionPlan2 = (ObjectQueryExecutionPlan)null;
if (queryCacheManager.TryCacheLookup <LinqQueryCacheKey, ObjectQueryExecutionPlan>(key1, out queryExecutionPlan2))
{
queryExecutionPlan1 = queryExecutionPlan2;
}
}
if (queryExecutionPlan1 == null)
{
queryExecutionPlan1 = this._objectQueryExecutionPlanFactory.Prepare(this.ObjectContext, DbQueryCommandTree.FromValidExpression(this.ObjectContext.MetadataWorkspace, DataSpace.CSpace, dbExpression, !this._useCSharpNullComparisonBehavior), this.ElementType, mergeOption, this.EffectiveStreamingBehavior, expressionConverter.PropagatedSpan, (IEnumerable <Tuple <ObjectParameter, QueryParameterExpression> >)null, expressionConverter.AliasGenerator);
if (key1 != null)
{
QueryCacheEntry inQueryCacheEntry = new QueryCacheEntry((QueryCacheKey)key1, (object)queryExecutionPlan1);
QueryCacheEntry outQueryCacheEntry = (QueryCacheEntry)null;
if (queryCacheManager.TryLookupAndAdd(inQueryCacheEntry, out outQueryCacheEntry))
{
queryExecutionPlan1 = (ObjectQueryExecutionPlan)outQueryCacheEntry.GetTarget();
}
}
}
this._cachedPlan = queryExecutionPlan1;
}
if (this._linqParameters != null)
{
foreach (Tuple <ObjectParameter, QueryParameterExpression> linqParameter in this._linqParameters)
{
ObjectParameter objectParameter = linqParameter.Item1;
QueryParameterExpression parameterExpression = linqParameter.Item2;
if (parameterExpression != null)
{
objectParameter.Value = parameterExpression.EvaluateParameter((object[])null);
}
}
}
return(queryExecutionPlan1);
}
internal DbQueryCommandTree GenerateCqt()
{
return(DbQueryCommandTree.FromValidExpression(this.m_mappingItemCollection.Workspace, DataSpace.SSpace, this.GenerateCqlBlockTree().AsCqt(true), true));
}
internal override ObjectQueryExecutionPlan GetExecutionPlan(MergeOption?forMergeOption)
{
Debug.Assert(Span == null, "Include span specified on compiled LINQ-based ObjectQuery instead of within the expression tree?");
Debug.Assert(_cachedPlan == null, "Cached plan should not be set on compiled LINQ queries");
ObjectQueryExecutionPlan plan = null;
var cacheEntry = _cacheEntry;
var useCSharpNullComparisonBehavior = ObjectContext.ContextOptions.UseCSharpNullComparisonBehavior;
var disableFilterOverProjectionSimplificationForCustomFunctions = ObjectContext.ContextOptions.DisableFilterOverProjectionSimplificationForCustomFunctions;
if (cacheEntry != null)
{
// The cache entry has already been retrieved, so compute the effective merge option with the following precedence:
// 1. The merge option specified as the argument to Execute(MergeOption), and so to this method
// 2. The merge option set using ObjectQuery.MergeOption
// 3. The propagated merge option as recorded in the cache entry
// 4. The global default merge option.
var mergeOption = EnsureMergeOption(forMergeOption, UserSpecifiedMergeOption, cacheEntry.PropagatedMergeOption);
// Ask for the corresponding execution plan
plan = cacheEntry.GetExecutionPlan(mergeOption, useCSharpNullComparisonBehavior);
if (plan == null)
{
// Convert the LINQ expression to produce a command tree
var converter = CreateExpressionConverter();
var queryExpression = converter.Convert();
var parameters = converter.GetParameters();
// Prepare the execution plan using the command tree and the computed effective merge option
var tree = DbQueryCommandTree.FromValidExpression(
ObjectContext.MetadataWorkspace, DataSpace.CSpace, queryExpression, !useCSharpNullComparisonBehavior, disableFilterOverProjectionSimplificationForCustomFunctions);
plan = _objectQueryExecutionPlanFactory.Prepare(
ObjectContext, tree, ElementType, mergeOption, EffectiveStreamingBehavior, converter.PropagatedSpan, parameters,
converter.AliasGenerator);
// Update and retrieve the execution plan
plan = cacheEntry.SetExecutionPlan(plan, useCSharpNullComparisonBehavior);
}
}
else
{
// This instance does not yet have a reference to a cache entry.
// First, attempt to retrieve an existing cache entry.
var cacheManager = ObjectContext.MetadataWorkspace.GetQueryCacheManager();
var cacheKey = new CompiledQueryCacheKey(_cacheToken);
if (cacheManager.TryCacheLookup(cacheKey, out cacheEntry))
{
// An entry was found in the cache, so compute the effective merge option based on its propagated merge option,
// and use the UseCSharpNullComparisonBehavior flag to retrieve the corresponding execution plan.
_cacheEntry = cacheEntry;
var mergeOption = EnsureMergeOption(forMergeOption, UserSpecifiedMergeOption, cacheEntry.PropagatedMergeOption);
plan = cacheEntry.GetExecutionPlan(mergeOption, useCSharpNullComparisonBehavior);
}
// If no cache entry was found or if the cache entry did not contain the required execution plan, the plan is still null at this point.
if (plan == null)
{
// The execution plan needs to be produced, so create an appropriate expression converter and generate the query command tree.
var converter = CreateExpressionConverter();
var queryExpression = converter.Convert();
var parameters = converter.GetParameters();
var tree = DbQueryCommandTree.FromValidExpression(
ObjectContext.MetadataWorkspace, DataSpace.CSpace, queryExpression, !useCSharpNullComparisonBehavior, disableFilterOverProjectionSimplificationForCustomFunctions);
// If a cache entry for this compiled query's cache key was not successfully retrieved, then it must be created now.
// Note that this is only possible after converting the LINQ expression and discovering the propagated merge option,
// which is required in order to create the cache entry.
if (cacheEntry == null)
{
// Create the cache entry using this instance's cache token and the propagated merge option (which may be null)
cacheEntry = new CompiledQueryCacheEntry(cacheKey, converter.PropagatedMergeOption);
// Attempt to add the entry to the cache. If an entry was added in the meantime, use that entry instead.
QueryCacheEntry foundEntry;
if (cacheManager.TryLookupAndAdd(cacheEntry, out foundEntry))
{
cacheEntry = (CompiledQueryCacheEntry)foundEntry;
}
// We now have a cache entry, so hold onto it for future use.
_cacheEntry = cacheEntry;
}
// Recompute the effective merge option in case a cache entry was just constructed above
var mergeOption = EnsureMergeOption(forMergeOption, UserSpecifiedMergeOption, cacheEntry.PropagatedMergeOption);
// Ask the (retrieved or constructed) cache entry for the corresponding execution plan.
plan = cacheEntry.GetExecutionPlan(mergeOption, useCSharpNullComparisonBehavior);
if (plan == null)
{
// The plan is not present, so prepare it now using the computed effective merge option
plan = _objectQueryExecutionPlanFactory.Prepare(
ObjectContext, tree, ElementType, mergeOption, EffectiveStreamingBehavior, converter.PropagatedSpan, parameters,
converter.AliasGenerator);
// Update the execution plan on the cache entry.
// If the execution plan was set in the meantime, SetExecutionPlan will return that value, otherwise it will return 'plan'.
plan = cacheEntry.SetExecutionPlan(plan, useCSharpNullComparisonBehavior);
}
}
}
// Get parameters from the plan and set them.
var currentParams = EnsureParameters();
if (plan.CompiledQueryParameters != null &&
plan.CompiledQueryParameters.Any())
{
currentParams.SetReadOnly(false);
currentParams.Clear();
foreach (var pair in plan.CompiledQueryParameters)
{
// Parameters retrieved from the CompiledQueryParameters collection must be cloned before being added to the query.
// The cached plan is shared and when used in multithreaded scenarios failing to clone the parameter would result
// in the code below updating the values of shared parameter instances saved in the cached plan and used by all
// queries using that plan, regardless of the values they were actually invoked with, causing incorrect results
// when those queries were later executed.
//
var convertedParam = pair.Item1.ShallowCopy();
var parameterExpression = pair.Item2;
currentParams.Add(convertedParam);
if (parameterExpression != null)
{
convertedParam.Value = parameterExpression.EvaluateParameter(_parameterValues);
}
}
}
currentParams.SetReadOnly(true);
Debug.Assert(plan != null, "Failed to produce an execution plan?");
return(plan);
}
internal override ObjectQueryExecutionPlan GetExecutionPlan(
MergeOption?forMergeOption)
{
MergeOption mergeOption = ObjectQueryState.EnsureMergeOption(forMergeOption, this.UserSpecifiedMergeOption);
ObjectQueryExecutionPlan queryExecutionPlan1 = this._cachedPlan;
if (queryExecutionPlan1 != null)
{
if (queryExecutionPlan1.MergeOption == mergeOption && queryExecutionPlan1.Streaming == this.EffectiveStreamingBehavior)
{
return(queryExecutionPlan1);
}
queryExecutionPlan1 = (ObjectQueryExecutionPlan)null;
}
QueryCacheManager queryCacheManager = (QueryCacheManager)null;
EntitySqlQueryCacheKey key = (EntitySqlQueryCacheKey)null;
if (this.PlanCachingEnabled)
{
key = new EntitySqlQueryCacheKey(this.ObjectContext.DefaultContainerName, this._queryText, this.Parameters == null ? 0 : this.Parameters.Count, this.Parameters == null ? (string)null : this.Parameters.GetCacheKey(), this.Span == null ? (string)null : this.Span.GetCacheKey(), mergeOption, this.EffectiveStreamingBehavior, this.ElementType);
queryCacheManager = this.ObjectContext.MetadataWorkspace.GetQueryCacheManager();
ObjectQueryExecutionPlan queryExecutionPlan2 = (ObjectQueryExecutionPlan)null;
if (queryCacheManager.TryCacheLookup <EntitySqlQueryCacheKey, ObjectQueryExecutionPlan>(key, out queryExecutionPlan2))
{
queryExecutionPlan1 = queryExecutionPlan2;
}
}
if (queryExecutionPlan1 == null)
{
queryExecutionPlan1 = this._objectQueryExecutionPlanFactory.Prepare(this.ObjectContext, DbQueryCommandTree.FromValidExpression(this.ObjectContext.MetadataWorkspace, DataSpace.CSpace, this.Parse(), true), this.ElementType, mergeOption, this.EffectiveStreamingBehavior, this.Span, (IEnumerable <Tuple <ObjectParameter, QueryParameterExpression> >)null, DbExpressionBuilder.AliasGenerator);
if (key != null)
{
QueryCacheEntry inQueryCacheEntry = new QueryCacheEntry((QueryCacheKey)key, (object)queryExecutionPlan1);
QueryCacheEntry outQueryCacheEntry = (QueryCacheEntry)null;
if (queryCacheManager.TryLookupAndAdd(inQueryCacheEntry, out outQueryCacheEntry))
{
queryExecutionPlan1 = (ObjectQueryExecutionPlan)outQueryCacheEntry.GetTarget();
}
}
}
if (this.Parameters != null)
{
this.Parameters.SetReadOnly(true);
}
this._cachedPlan = queryExecutionPlan1;
return(queryExecutionPlan1);
}
internal override ObjectQueryExecutionPlan GetExecutionPlan(MergeOption?forMergeOption)
{
// Determine the required merge option, with the following precedence:
// 1. The merge option specified to Execute(MergeOption) as forMergeOption.
// 2. The merge option set via ObjectQuery.MergeOption.
// 3. The global default merge option.
var mergeOption = EnsureMergeOption(forMergeOption, UserSpecifiedMergeOption);
// If a cached plan is present, then it can be reused if it has the required merge option and streaming behavior
// (since span and parameters cannot change between executions). However, if the cached
// plan does not have the required merge option we proceed as if it were not present.
var plan = _cachedPlan;
if (plan != null)
{
if (plan.MergeOption == mergeOption &&
plan.Streaming == EffectiveStreamingBehavior)
{
return(plan);
}
else
{
plan = null;
}
}
// There is no cached plan (or it was cleared), so the execution plan must be retrieved from
// the global query cache (if plan caching is enabled) or rebuilt for the required merge option.
QueryCacheManager cacheManager = null;
EntitySqlQueryCacheKey cacheKey = null;
if (PlanCachingEnabled)
{
// Create a new cache key that reflects the current state of the Parameters collection
// and the Span object (if any), and uses the specified merge option.
cacheKey = new EntitySqlQueryCacheKey(
ObjectContext.DefaultContainerName,
_queryText,
(null == Parameters ? 0 : Parameters.Count),
(null == Parameters ? null : Parameters.GetCacheKey()),
(null == Span ? null : Span.GetCacheKey()),
mergeOption,
EffectiveStreamingBehavior,
ElementType);
cacheManager = ObjectContext.MetadataWorkspace.GetQueryCacheManager();
ObjectQueryExecutionPlan executionPlan = null;
if (cacheManager.TryCacheLookup(cacheKey, out executionPlan))
{
plan = executionPlan;
}
}
if (plan == null)
{
// Either caching is not enabled or the execution plan was not found in the cache
var queryExpression = Parse();
Debug.Assert(queryExpression != null, "EntitySqlQueryState.Parse returned null expression?");
var tree = DbQueryCommandTree.FromValidExpression(
ObjectContext.MetadataWorkspace, DataSpace.CSpace, queryExpression,
useDatabaseNullSemantics: true);
plan = _objectQueryExecutionPlanFactory.Prepare(
ObjectContext, tree, ElementType, mergeOption, EffectiveStreamingBehavior, Span, null,
DbExpressionBuilder.AliasGenerator);
// If caching is enabled then update the cache now.
// Note: the logic is the same as in ELinqQueryState.
if (cacheKey != null)
{
var newEntry = new QueryCacheEntry(cacheKey, plan);
QueryCacheEntry foundEntry = null;
if (cacheManager.TryLookupAndAdd(newEntry, out foundEntry))
{
// If TryLookupAndAdd returns 'true' then the entry was already present in the cache when the attempt to add was made.
// In this case the existing execution plan should be used.
plan = (ObjectQueryExecutionPlan)foundEntry.GetTarget();
}
}
}
if (Parameters != null)
{
Parameters.SetReadOnly(true);
}
// Update the cached plan with the newly retrieved/prepared plan
_cachedPlan = plan;
// Return the execution plan
return(plan);
}
internal static ObjectQueryExecutionPlan Prepare(ObjectContext context, DbQueryCommandTree tree, Type elementType, MergeOption mergeOption, Span span, CompiledQueryParameters compiledQueryParameters, AliasGenerator aliasGenerator)
{
TypeUsage treeResultType = tree.Query.ResultType;
// Rewrite this tree for Span?
DbExpression spannedQuery = null;
SpanIndex spanInfo;
if (ObjectSpanRewriter.TryRewrite(tree, span, mergeOption, aliasGenerator, out spannedQuery, out spanInfo))
{
tree = DbQueryCommandTree.FromValidExpression(tree.MetadataWorkspace, tree.DataSpace, spannedQuery);
}
else
{
spanInfo = null;
}
DbConnection connection = context.Connection;
DbCommandDefinition definition = null;
// The connection is required to get to the CommandDefinition builder.
if (connection == null)
{
throw EntityUtil.InvalidOperation(System.Data.Entity.Strings.ObjectQuery_InvalidConnection);
}
DbProviderServices services = DbProviderServices.GetProviderServices(connection);
try
{
definition = services.CreateCommandDefinition(tree);
}
catch (EntityCommandCompilationException)
{
// If we're running against EntityCommand, we probably already caught the providers'
// exception and wrapped it, we don't want to do that again, so we'll just rethrow
// here instead.
throw;
}
catch (Exception e)
{
// we should not be wrapping all exceptions
if (EntityUtil.IsCatchableExceptionType(e))
{
// we don't wan't folks to have to know all the various types of exceptions that can
// occur, so we just rethrow a CommandDefinitionException and make whatever we caught
// the inner exception of it.
throw EntityUtil.CommandCompilation(System.Data.Entity.Strings.EntityClient_CommandDefinitionPreparationFailed, e);
}
throw;
}
if (definition == null)
{
throw EntityUtil.ProviderDoesNotSupportCommandTrees();
}
EntityCommandDefinition entityDefinition = (EntityCommandDefinition)definition;
QueryCacheManager cacheManager = context.Perspective.MetadataWorkspace.GetQueryCacheManager();
ShaperFactory shaperFactory = ShaperFactory.Create(elementType, cacheManager, entityDefinition.CreateColumnMap(null),
context.MetadataWorkspace, spanInfo, mergeOption, false);
// attempt to determine entity information for this query (e.g. which entity type and which entity set)
//EntityType rootEntityType = null;
EntitySet singleEntitySet = null;
if (treeResultType.EdmType.BuiltInTypeKind == BuiltInTypeKind.CollectionType)
{
// determine if the entity set is unambiguous given the entity type
if (null != entityDefinition.EntitySets)
{
foreach (EntitySet entitySet in entityDefinition.EntitySets)
{
if (null != entitySet)
{
if (entitySet.ElementType.IsAssignableFrom(((CollectionType)treeResultType.EdmType).TypeUsage.EdmType))
{
if (singleEntitySet == null)
{
// found a single match
singleEntitySet = entitySet;
}
else
{
// there's more than one matching entity set
singleEntitySet = null;
break;
}
}
}
}
}
}
return(new ObjectQueryExecutionPlan(definition, shaperFactory, treeResultType, mergeOption, singleEntitySet, compiledQueryParameters));
}
internal override ObjectQueryExecutionPlan GetExecutionPlan(
MergeOption?forMergeOption)
{
ObjectQueryExecutionPlan queryExecutionPlan = (ObjectQueryExecutionPlan)null;
CompiledQueryCacheEntry compiledQueryCacheEntry = this._cacheEntry;
bool comparisonBehavior = this.ObjectContext.ContextOptions.UseCSharpNullComparisonBehavior;
if (compiledQueryCacheEntry != null)
{
MergeOption mergeOption = ObjectQueryState.EnsureMergeOption(forMergeOption, this.UserSpecifiedMergeOption, compiledQueryCacheEntry.PropagatedMergeOption);
queryExecutionPlan = compiledQueryCacheEntry.GetExecutionPlan(mergeOption, comparisonBehavior);
if (queryExecutionPlan == null)
{
ExpressionConverter expressionConverter = this.CreateExpressionConverter();
DbExpression query = expressionConverter.Convert();
IEnumerable <Tuple <ObjectParameter, QueryParameterExpression> > parameters = expressionConverter.GetParameters();
ObjectQueryExecutionPlan newPlan = this._objectQueryExecutionPlanFactory.Prepare(this.ObjectContext, DbQueryCommandTree.FromValidExpression(this.ObjectContext.MetadataWorkspace, DataSpace.CSpace, query, !comparisonBehavior), this.ElementType, mergeOption, this.EffectiveStreamingBehavior, expressionConverter.PropagatedSpan, parameters, expressionConverter.AliasGenerator);
queryExecutionPlan = compiledQueryCacheEntry.SetExecutionPlan(newPlan, comparisonBehavior);
}
}
else
{
QueryCacheManager queryCacheManager = this.ObjectContext.MetadataWorkspace.GetQueryCacheManager();
CompiledQueryCacheKey key = new CompiledQueryCacheKey(this._cacheToken);
if (queryCacheManager.TryCacheLookup <CompiledQueryCacheKey, CompiledQueryCacheEntry>(key, out compiledQueryCacheEntry))
{
this._cacheEntry = compiledQueryCacheEntry;
MergeOption mergeOption = ObjectQueryState.EnsureMergeOption(forMergeOption, this.UserSpecifiedMergeOption, compiledQueryCacheEntry.PropagatedMergeOption);
queryExecutionPlan = compiledQueryCacheEntry.GetExecutionPlan(mergeOption, comparisonBehavior);
}
if (queryExecutionPlan == null)
{
ExpressionConverter expressionConverter = this.CreateExpressionConverter();
DbExpression query = expressionConverter.Convert();
IEnumerable <Tuple <ObjectParameter, QueryParameterExpression> > parameters = expressionConverter.GetParameters();
DbQueryCommandTree tree = DbQueryCommandTree.FromValidExpression(this.ObjectContext.MetadataWorkspace, DataSpace.CSpace, query, !comparisonBehavior);
if (compiledQueryCacheEntry == null)
{
compiledQueryCacheEntry = new CompiledQueryCacheEntry((QueryCacheKey)key, expressionConverter.PropagatedMergeOption);
QueryCacheEntry outQueryCacheEntry;
if (queryCacheManager.TryLookupAndAdd((QueryCacheEntry)compiledQueryCacheEntry, out outQueryCacheEntry))
{
compiledQueryCacheEntry = (CompiledQueryCacheEntry)outQueryCacheEntry;
}
this._cacheEntry = compiledQueryCacheEntry;
}
MergeOption mergeOption = ObjectQueryState.EnsureMergeOption(forMergeOption, this.UserSpecifiedMergeOption, compiledQueryCacheEntry.PropagatedMergeOption);
queryExecutionPlan = compiledQueryCacheEntry.GetExecutionPlan(mergeOption, comparisonBehavior);
if (queryExecutionPlan == null)
{
ObjectQueryExecutionPlan newPlan = this._objectQueryExecutionPlanFactory.Prepare(this.ObjectContext, tree, this.ElementType, mergeOption, this.EffectiveStreamingBehavior, expressionConverter.PropagatedSpan, parameters, expressionConverter.AliasGenerator);
queryExecutionPlan = compiledQueryCacheEntry.SetExecutionPlan(newPlan, comparisonBehavior);
}
}
}
ObjectParameterCollection parameterCollection = this.EnsureParameters();
if (queryExecutionPlan.CompiledQueryParameters != null && queryExecutionPlan.CompiledQueryParameters.Any <Tuple <ObjectParameter, QueryParameterExpression> >())
{
parameterCollection.SetReadOnly(false);
parameterCollection.Clear();
foreach (Tuple <ObjectParameter, QueryParameterExpression> compiledQueryParameter in queryExecutionPlan.CompiledQueryParameters)
{
ObjectParameter objectParameter = compiledQueryParameter.Item1.ShallowCopy();
QueryParameterExpression parameterExpression = compiledQueryParameter.Item2;
parameterCollection.Add(objectParameter);
if (parameterExpression != null)
{
objectParameter.Value = parameterExpression.EvaluateParameter(this._parameterValues);
}
}
}
parameterCollection.SetReadOnly(true);
return(queryExecutionPlan);
}
