protected virtual void AddRelation <T, TRelation>(ICollectionEntityGraphNode <T, TRelation> node, Frame frame)
{
var query = this.Database.QueryCache.Add(node.Relation.MappingTable);
var parameters = this.GetParameters(frame, node.Relation);
this.Database.Execute(query, parameters, this.Transaction);
}
protected virtual void DeleteRelation <T, TRelation>(ICollectionEntityGraphNode <T, TRelation> node, Frame frame)
{
var query = this.Database.QueryCache.GetOrAdd(
new DatabaseQueryTableCacheKey(
node.Relation.MappingTable,
DatabaseQueryCache.DELETE
),
() =>
{
var builder = this.Database.QueryFactory.Build();
var columns = node.Relation.Expression.GetColumnMap();
builder.Delete.Touch();
builder.Source.AddTable(node.Relation.MappingTable);
builder.Filter.AddColumns(columns[node.Relation.MappingTable]);
return(builder.Build());
}
);
var parameters = this.GetParameters(frame, node.Relation);
this.Database.Execute(query, parameters, this.Transaction);
}
protected virtual EntityAction OnVisit <T, TRelation>(ICollectionEntityGraphNode <T, TRelation> node, Frame <T> frame)
{
var result = EntityAction.None;
var difference = EntityDiffer.Instance.GetDifference <T, TRelation>(node.Relation, frame.Persisted, frame.Updated);
foreach (var element in difference.Added.Concat(difference.Updated))
{
result |= this.OnVisit(node, new Frame <TRelation>(frame, element.Persisted, element.Updated));
if (result.HasFlag(EntityAction.Added) && node.Relation.Flags.GetMultiplicity() == RelationFlags.ManyToMany)
{
this.AddRelation(node, new Frame <TRelation>(frame, element.Persisted, element.Updated));
}
}
foreach (var element in difference.Deleted)
{
if (node.Relation.Flags.GetMultiplicity() == RelationFlags.ManyToMany)
{
this.DeleteRelation(node, new Frame <TRelation>(frame, element.Persisted, element.Updated));
}
result |= this.OnVisit(node, new Frame <TRelation>(frame, element.Persisted, element.Updated));
}
return(result);
}
protected virtual void OnVisit <T, TRelation>(IEntityEnumeratorBuffer buffer, IEntityEnumeratorSink sink, ICollectionEntityGraphNode <T, TRelation> node)
{
if (!buffer.Exists(node.Parent.Table) || !buffer.Exists(node.Table))
{
return;
}
var parent = (T)buffer.Get(node.Parent.Table);
var child = (TRelation)buffer.Get(node.Table);
var sequence = node.Relation.Accessor.Get(parent);
if (sequence == null)
{
throw new NotImplementedException();
}
else
{
sequence.Add(child);
}
}