protected override Expression VisitSubQuery(SubQueryExpression expression)
{
var oldParentSelector = _parentSelector;
_parentSelector = expression.QueryModel.SelectClause.Selector;
expression.QueryModel.TransformExpressions(Visit);
_parentSelector = oldParentSelector;
var querySourceReferenceExpression
= expression.QueryModel.SelectClause.Selector
as QuerySourceReferenceExpression;
if (querySourceReferenceExpression != null)
{
var querySourceTracingExpressionVisitor = new QuerySourceTracingExpressionVisitor();
var resultQuerySource
= querySourceTracingExpressionVisitor
.FindResultQuerySourceReferenceExpression(
_parentSelector,
querySourceReferenceExpression.ReferencedQuerySource);
if ((resultQuerySource == null) &&
!(expression.QueryModel.ResultOperators.LastOrDefault() is OfTypeResultOperator))
{
_querySources[querySourceReferenceExpression.ReferencedQuerySource]--;
}
}
return(expression);
}
/// <summary>
/// This API supports the Entity Framework Core infrastructure and is not intended to be used
/// directly from your code. This API may change or be removed in future releases.
/// </summary>
public EagerLoadingExpressionVisitor(
QueryCompilationContext queryCompilationContext,
IQuerySourceTracingExpressionVisitorFactory querySourceTracingExpressionVisitorFactory)
{
_queryCompilationContext = queryCompilationContext;
_querySourceTracingExpressionVisitor = querySourceTracingExpressionVisitorFactory.Create();
}
/// <summary>
/// This API supports the Entity Framework Core infrastructure and is not intended to be used
/// directly from your code. This API may change or be removed in future releases.
/// </summary>
protected override Expression VisitSubQuery(SubQueryExpression expression)
{
var oldParentSelector = _selector;
var oldQueryModel = _queryModel;
_selector = expression.QueryModel.SelectClause.Selector;
_queryModel = expression.QueryModel;
_queryModel.TransformExpressions(Visit);
_selector = oldParentSelector;
_queryModel = oldQueryModel;
var querySourceReferenceExpression
= expression.QueryModel.SelectClause.Selector
as QuerySourceReferenceExpression;
if (querySourceReferenceExpression != null)
{
var querySourceTracingExpressionVisitor = new QuerySourceTracingExpressionVisitor();
if (expression.QueryModel.ResultOperators.LastOrDefault() is DefaultIfEmptyResultOperator)
{
var underlyingQuerySource = (((querySourceReferenceExpression.ReferencedQuerySource as MainFromClause)
?.FromExpression as QuerySourceReferenceExpression)
?.ReferencedQuerySource as GroupJoinClause)?.JoinClause;
if (underlyingQuerySource != null)
{
AddQuerySource(underlyingQuerySource);
}
}
var resultQuerySource
= querySourceTracingExpressionVisitor
.FindResultQuerySourceReferenceExpression(
_selector,
querySourceReferenceExpression.ReferencedQuerySource);
if ((resultQuerySource == null) &&
!(expression.QueryModel.ResultOperators.LastOrDefault() is OfTypeResultOperator))
{
_querySources[querySourceReferenceExpression.ReferencedQuerySource]--;
}
foreach (var sourceExpression
in _queryModel.ResultOperators.Select(SetResultOperationSourceExpression).Where(e => e != null))
{
if (sourceExpression.Equals(expression))
{
var parentQuerySource = _selector as QuerySourceReferenceExpression;
if ((parentQuerySource != null) &&
(_querySources[parentQuerySource.ReferencedQuerySource] > 0) &&
(parentQuerySource.Type == querySourceReferenceExpression.Type))
{
_querySources[querySourceReferenceExpression.ReferencedQuerySource]++;
}
}
}
}
return(expression);
}
