private Expression LiftSubQuery(
IQuerySource querySource, Expression itemsExpression, QueryModel queryModel, Expression expression)
{
SelectExpression subSelectExpression;
if (_subqueriesBySource.TryGetValue(querySource, out subSelectExpression) &&
(!subSelectExpression.OrderBy.Any() ||
subSelectExpression.Limit != null))
{
subSelectExpression.PushDownSubquery().QuerySource = querySource;
AddQuery(querySource, subSelectExpression);
_subqueriesBySource.Remove(querySource);
var shapedQueryMethodExpression
= new ShapedQueryFindingExpressionVisitor(QueryCompilationContext)
.Find(expression);
var shaperLambda = (LambdaExpression)shapedQueryMethodExpression.Arguments[2];
var shaperMethodCall = (MethodCallExpression)shaperLambda.Body;
var shaperMethod = shaperMethodCall.Method;
var shaperMethodArgs = shaperMethodCall.Arguments.ToList();
if (!QueryCompilationContext.QuerySourceRequiresMaterialization(querySource) &&
shaperMethod.MethodIsClosedFormOf(RelationalEntityQueryableExpressionVisitor.CreateEntityMethodInfo))
{
shaperMethod = RelationalEntityQueryableExpressionVisitor.CreateValueBufferMethodInfo;
shaperMethodArgs.RemoveRange(5, 5);
}
else
{
subSelectExpression.ExplodeStarProjection();
}
var innerQuerySource = (IQuerySource)((ConstantExpression)shaperMethodArgs[0]).Value;
foreach (var queryAnnotation
in QueryCompilationContext.QueryAnnotations
.Where(qa => qa.QuerySource == innerQuerySource))
{
queryAnnotation.QuerySource = querySource;
}
shaperMethodArgs[0] = Expression.Constant(querySource);
var querySourceReferenceExpression
= queryModel.SelectClause.Selector as QuerySourceReferenceExpression;
if (querySourceReferenceExpression != null &&
querySourceReferenceExpression.ReferencedQuerySource == querySource)
{
var subQueryModel = (itemsExpression as SubQueryExpression)?.QueryModel;
if (subQueryModel != null)
{
queryModel.SelectClause.Selector = subQueryModel.SelectClause.Selector;
QueryCompilationContext.QuerySourceMapping
.ReplaceMapping(
subQueryModel.MainFromClause,
QueryResultScope.GetResult(
QueryResultScopeParameter,
querySource,
shaperMethod.ReturnType.GenericTypeArguments[0]));
}
}
return(Expression.Call(
QueryCompilationContext.QueryMethodProvider.ShapedQueryMethod
.MakeGenericMethod(shaperMethod.ReturnType),
shapedQueryMethodExpression.Arguments[0],
shapedQueryMethodExpression.Arguments[1],
Expression.Lambda(
Expression.Call(shaperMethod, shaperMethodArgs),
shaperLambda.Parameters[0])));
}
return(expression);
}
public override void VisitJoinClause(JoinClause joinClause, QueryModel queryModel, int index)
{
Check.NotNull(joinClause, nameof(joinClause));
Check.NotNull(queryModel, nameof(queryModel));
var previousQuerySource = FindPreviousQuerySource(queryModel, index);
var previousSelectExpression
= previousQuerySource != null
? TryGetQuery(previousQuerySource)
: null;
var previousSelectProjectionCount
= previousSelectExpression?.Projection.Count ?? -1;
base.VisitJoinClause(joinClause, queryModel, index);
if (previousSelectExpression != null)
{
var selectExpression = TryGetQuery(joinClause);
if (selectExpression != null)
{
var filteringExpressionVisitor
= new SqlTranslatingExpressionVisitor(this, targetSelectExpression: null);
var predicate
= filteringExpressionVisitor
.Visit(
Expression.Equal(
joinClause.OuterKeySelector,
joinClause.InnerKeySelector));
if (predicate != null)
{
_queriesBySource.Remove(joinClause);
previousSelectExpression.RemoveRangeFromProjection(previousSelectProjectionCount);
var innerJoinExpression
= previousSelectExpression
.AddInnerJoin(
selectExpression.Tables.Single(),
QueryCompilationContext
.QuerySourceRequiresMaterialization(joinClause)
? selectExpression.Projection
: Enumerable.Empty <Expression>());
innerJoinExpression.Predicate = predicate;
Expression
= new QueryFlatteningExpressionVisitor(
previousQuerySource,
joinClause,
QueryCompilationContext,
previousSelectProjectionCount,
LinqOperatorProvider.Join)
.Visit(Expression);
}
else
{
previousSelectExpression.RemoveRangeFromProjection(previousSelectProjectionCount);
}
}
}
}
protected virtual void OptimizeJoinClause(
[NotNull] JoinClause joinClause,
[NotNull] QueryModel queryModel,
int index,
[NotNull] Action baseVisitAction,
[NotNull] MethodInfo operatorToFlatten,
bool outerJoin = false)
{
Check.NotNull(joinClause, nameof(joinClause));
Check.NotNull(queryModel, nameof(queryModel));
Check.NotNull(baseVisitAction, nameof(baseVisitAction));
Check.NotNull(operatorToFlatten, nameof(operatorToFlatten));
var previousQuerySource = FindPreviousQuerySource(queryModel, index);
var previousSelectExpression
= previousQuerySource != null
? TryGetQuery(previousQuerySource)
: null;
var previousSelectProjectionCount
= previousSelectExpression?.Projection.Count ?? -1;
baseVisitAction();
if (previousSelectExpression != null)
{
var selectExpression = TryGetQuery(joinClause);
if (selectExpression != null)
{
var sqlTranslatingExpressionVisitor = new SqlTranslatingExpressionVisitor(this);
var predicate
= sqlTranslatingExpressionVisitor
.Visit(
Expression.Equal(
joinClause.OuterKeySelector,
joinClause.InnerKeySelector));
if (predicate != null)
{
_queriesBySource.Remove(joinClause);
previousSelectExpression.RemoveRangeFromProjection(previousSelectProjectionCount);
var tableExpression = selectExpression.Tables.Single();
var projection
= QueryCompilationContext
.QuerySourceRequiresMaterialization(joinClause)
? selectExpression.Projection
: Enumerable.Empty <Expression>();
var joinExpression
= !outerJoin
? previousSelectExpression.AddInnerJoin(tableExpression, projection)
: previousSelectExpression.AddOuterJoin(tableExpression, projection);
joinExpression.Predicate = predicate;
Expression
= new QueryFlatteningExpressionVisitor(
previousQuerySource,
joinClause,
QueryCompilationContext,
previousSelectProjectionCount,
operatorToFlatten)
.Visit(Expression);
}
else
{
previousSelectExpression
.RemoveRangeFromProjection(previousSelectProjectionCount);
}
}
}
}
private Expression LiftSubQuery(
IQuerySource querySource, Expression itemsExpression, QueryModel queryModel, Expression expression)
{
var subQueryExpression = itemsExpression as SubQueryExpression;
if (subQueryExpression == null)
{
return(expression);
}
var subQueryModelVisitor
= (RelationalQueryModelVisitor)QueryCompilationContext.CreateQueryModelVisitor(this);
subQueryModelVisitor.VisitSubQueryModel(subQueryExpression.QueryModel);
SelectExpression subSelectExpression = null;
if (subQueryModelVisitor.Queries.Count == 1 &&
!subQueryModelVisitor.RequiresClientFilter &&
!subQueryModelVisitor.RequiresClientSelectMany &&
!subQueryModelVisitor.RequiresClientProjection &&
!subQueryModelVisitor.RequiresClientResultOperator)
{
subSelectExpression = subQueryModelVisitor.Queries.First();
}
if (subSelectExpression != null &&
(!subSelectExpression.OrderBy.Any() ||
subSelectExpression.Limit != null) &&
(QueryCompilationContext.IsCrossApplySupported ||
(!subSelectExpression.IsCorrelated() ||
!(querySource is AdditionalFromClause))))
{
subSelectExpression.PushDownSubquery().QuerySource = querySource;
AddQuery(querySource, subSelectExpression);
var shapedQueryMethodExpression
= new ShapedQueryFindingExpressionVisitor(QueryCompilationContext)
.Find(subQueryModelVisitor.Expression);
var shaperLambda = (LambdaExpression)shapedQueryMethodExpression.Arguments[2];
var shaperMethodCall = (MethodCallExpression)shaperLambda.Body;
var shaperMethod = shaperMethodCall.Method;
var shaperMethodArgs = shaperMethodCall.Arguments.ToList();
if (!QueryCompilationContext.QuerySourceRequiresMaterialization(querySource) &&
shaperMethod.MethodIsClosedFormOf(RelationalEntityQueryableExpressionVisitor.CreateEntityMethodInfo))
{
shaperMethod = RelationalEntityQueryableExpressionVisitor.CreateValueBufferMethodInfo;
shaperMethodArgs.RemoveRange(5, 5);
}
else
{
subSelectExpression.ExplodeStarProjection();
}
var innerQuerySource = (IQuerySource)((ConstantExpression)shaperMethodArgs[0]).Value;
foreach (var queryAnnotation
in QueryCompilationContext.QueryAnnotations
.Where(qa => qa.QuerySource == innerQuerySource))
{
queryAnnotation.QuerySource = querySource;
}
shaperMethodArgs[0] = Expression.Constant(querySource);
var querySourceReferenceExpression
= queryModel.SelectClause.Selector as QuerySourceReferenceExpression;
if (querySourceReferenceExpression != null &&
querySourceReferenceExpression.ReferencedQuerySource == querySource)
{
if (subQueryExpression.QueryModel != null)
{
queryModel.SelectClause.Selector = subQueryExpression.QueryModel.SelectClause.Selector;
QueryCompilationContext.QuerySourceMapping
.ReplaceMapping(
subQueryExpression.QueryModel.MainFromClause,
QueryResultScope.GetResult(
QueryResultScopeParameter,
querySource,
shaperMethod.ReturnType.GenericTypeArguments[0]));
}
}
return(Expression.Call(
QueryCompilationContext.QueryMethodProvider.ShapedQueryMethod
.MakeGenericMethod(shaperMethod.ReturnType),
shapedQueryMethodExpression.Arguments[0],
shapedQueryMethodExpression.Arguments[1],
Expression.Lambda(
Expression.Call(shaperMethod, shaperMethodArgs),
shaperLambda.Parameters[0])));
}
return(expression);
}
protected virtual void OptimizeJoinClause(
[NotNull] JoinClause joinClause,
[NotNull] QueryModel queryModel,
int index,
[NotNull] Action baseVisitAction,
[NotNull] MethodInfo operatorToFlatten,
bool outerJoin = false)
{
Check.NotNull(joinClause, nameof(joinClause));
Check.NotNull(queryModel, nameof(queryModel));
Check.NotNull(baseVisitAction, nameof(baseVisitAction));
Check.NotNull(operatorToFlatten, nameof(operatorToFlatten));
RequiresClientJoin = true;
var previousQuerySource = FindPreviousQuerySource(queryModel, index);
var previousSelectExpression
= previousQuerySource != null
? TryGetQuery(previousQuerySource)
: null;
var previousSelectProjectionCount
= previousSelectExpression?.Projection.Count ?? -1;
baseVisitAction();
if (previousSelectExpression != null)
{
var selectExpression = TryGetQuery(joinClause);
if (selectExpression != null)
{
var sqlTranslatingExpressionVisitor
= _sqlTranslatingExpressionVisitorFactory.Create(this);
var predicate
= sqlTranslatingExpressionVisitor
.Visit(
Expression.Equal(
joinClause.OuterKeySelector,
joinClause.InnerKeySelector));
if (predicate != null)
{
QueriesBySource.Remove(joinClause);
previousSelectExpression.RemoveRangeFromProjection(previousSelectProjectionCount);
var tableExpression = selectExpression.Tables.Single();
var projection
= QueryCompilationContext
.QuerySourceRequiresMaterialization(joinClause)
? selectExpression.Projection
: Enumerable.Empty <Expression>();
var joinExpression
= !outerJoin
? previousSelectExpression.AddInnerJoin(tableExpression, projection)
: previousSelectExpression.AddOuterJoin(tableExpression, projection);
joinExpression.Predicate = predicate;
if (outerJoin)
{
var outerJoinOrderingExtractor = new OuterJoinOrderingExtractor();
outerJoinOrderingExtractor.Visit(predicate);
foreach (var expression in outerJoinOrderingExtractor.Expressions)
{
previousSelectExpression
.AddToOrderBy(new Ordering(expression, OrderingDirection.Asc));
}
}
Expression
= _queryFlattenerFactory
.Create(
joinClause,
QueryCompilationContext,
operatorToFlatten,
previousSelectProjectionCount)
.Flatten((MethodCallExpression)Expression);
RequiresClientJoin = false;
}
}
}
if (RequiresClientJoin)
{
CheckClientEval(joinClause);
}
}