As you probably know, when inserting or removing records from collections supporting IBindingList, it is necessary to load the entire collection (that means constructing its persistent objects and their related objects graphs) from the database. It is an understandable requirement (we need to fire the IBindingList.ListChanged event with correct indices), but it might drive to some XPO customers crazy. For example, if we inserted or removed an object from an associated details collection containing a lot of complex objects, it might become a performance problem.
Though there has been an unofficial solution (based on the use of IList collections instead of collections of XPCollection type) available for many years, it was not final and had some drawbacks (the need to redesign persistent classes, inability to access Criteria and other features of the XPCollection, data binding limitations, etc.). Finally, improving the current state of affairs has also been one of the most popular requests our customers asked us for in recent years.
Our developers have managed to work around the limitation described above in version 11.2, and trust me, it is something you will notice immediately. Generally, XPCollection will perform significantly faster on inserting and deleting objects into and from a large associated 1-M details collection. Certainly, the exact speed improvement will depend on the collection size, the complexity of your objects graphs and other factors. Note that these changes do not affect M-M details collections at this time, because this is a more difficult case. We will research it the future.
To test it in action, I used a modified version of the test application (you can download it here) from my previous blog. See my results below:
11.1.7
11.2.1
As you see, it is ~100x faster on insert and ~10x faster on removal when the details collection was comprised of 10000 objects. These improvements will be more noticeable, the greater the size of the details collection.
Do you like the XPO improvements? Please let us know your opinion!
Happy XPOing!
Great news for 11.2
Anything that could improve performance is always welcome in my book.
Thanks guys.
will this improvement reduce memory consumption?
Great news for comprehensive business applications!
@Gustavo: Sure. If the whole collection is not loaded on adding or removing objects, then less memory (by the amount required to hold this collection) will be allocated.
Nice. Been waiting for this for a long time.
We are glad to hear that you liked these improvements, guys!
Why not remove IBindingList implementation from XPCollection if it slows down the performance? How many of your customers bind it directly to UI? UI should be separated from DB.
Thomas,
I would think many do. I sure do, especially in quick apps. Drop the collection component and hook it up to the Grid. Done.
Please get it released asap!!
Would be great if DevEx could split the XPCollection to have the "low level" and "high level GUI" parts.
I think that is Session.GetObjects() :)
Nate Laff,
GetCollection of XPBaseObject returns XPCollection :)
When this version will be released ?
Great News, because Im experiencing a huge performance issue. I m eager to get this version and see the improvements.
That really will help us! We are always making workarounds to solve this problem. 3 points basket !!!!