private void TryMarkSubQuery(SubQueryExpression expression)
{
var subQueryModel = expression.QueryModel;
subQueryModel.SelectClause.TransformExpressions(Visit);
if (CorrelatedSubqueryOptimizationValidator.CanTryOptimizeCorrelatedSubquery(subQueryModel))
{
// if the query passes validation it becomes a candidate for future optimization
// optimization can't always be performed, e.g. when client-eval is needed
// but we need to collect metadata (i.e. INavigations) before nav rewrite converts them into joins
_queryModelVisitor.BindNavigationPathPropertyExpression(
subQueryModel.MainFromClause.FromExpression,
(properties, querySource) =>
{
var collectionNavigation = properties.OfType <INavigation>().SingleOrDefault(n => n.IsCollection());
if (collectionNavigation != null)
{
_queryModelVisitor.QueryCompilationContext.RegisterCorrelatedSubqueryMetadata(
subQueryModel.MainFromClause,
_trackingQuery,
properties.OfType <INavigation>().First(),
collectionNavigation,
querySource);
return(expression);
}
return(default);
});
/// <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 VisitMember(MemberExpression memberExpression)
{
Check.NotNull(memberExpression, nameof(memberExpression));
var newMemberExpression = default(Expression);
if (_shouldInject)
{
newMemberExpression = _queryModelVisitor.BindNavigationPathPropertyExpression(
memberExpression,
(properties, querySource) =>
{
var collectionNavigation = properties.OfType <INavigation>().SingleOrDefault(n => n.IsCollection());
return(collectionNavigation != null
? InjectSubquery(memberExpression, collectionNavigation)
: default(Expression));
});
}
return(newMemberExpression ?? base.VisitMember(memberExpression));
}
protected override Expression VisitMember(MemberExpression node)
{
Check.NotNull(node, nameof(node));
return
(_queryModelVisitor.BindNavigationPathPropertyExpression(
node,
(properties, querySource) =>
{
var navigations = properties.OfType <INavigation>().ToList();
var collectionNavigation = navigations.SingleOrDefault(n => n.IsCollection());
return collectionNavigation != null
? InjectSubquery(node, collectionNavigation)
: default(Expression);
})
?? base.VisitMember(node));
}
/// <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 VisitMember(MemberExpression node)
=> _queryModelVisitor.BindNavigationPathPropertyExpression(
node,
(ps, qs) => RewritePropertyAccess(node, ps, qs)) ?? base.VisitMember(node);