VelocityDB & VelocityGraph

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VelocityDB Version 4.2.5 Release Notes

27. February 2015 Mats (0)

Placement fix, use IOptimizedPersistable.PlacementDatabaseNumber if overridden to return something other than Placement.DefaultPlacementDatabaseNumber. Fix for an [UseOidShort] issue.

Reference to object without opening

27. February 2015 ubique Question (0)

How can I add a reference to an object, if I know its oid, and I don't want to open it?

If I just do :

var referenceToObj = new EntityObject{ID = knownOID}
var newObj = new AnotherObject(referenceToObj);
session.Persist(newObj);

than both newObj is created and new object referenceToObj is created (and it is not desired). I think, that API ignores its ID property and looks at IsPersistent which returns false;

Descending sort in the Index field attribute

18. February 2015 ubique Feature Request (0)

Can you add the possibility to set descending sort  while using Index Attribute on the field? Something like [Index(descendingSort:true)]. 

As far I know, it is  possible to use descending sort with attribute on the class by prepending a minus, i.e. [Index("-indexField")]

VelocityDB Version 4.2.4 Release Notes

12. February 2015 Mats (0)

Guard against setting property values to null (instead remove Edge/Vertex property value) and add IOptimizedPersistable as a property type choice. Handle errors better on server side. Now removing objects from indices when deleting a database.


VelocityDB Version 4.2.2 Release Notes

4. February 2015 Mats (0)

Enable object caching by default (Make CacheEnum.Yes default in session constructors) and release all cached objects when a cached database is not up to date (updated by another session). This can have a dramatic impact on performance. One client saw elapsed time go from 15 minutes to 4 s.

VelocityDB Version 4.1 Release Notes

18. January 2015 Mats (0)

Added SessionBase.Compact() (not yet implemented for ServerClientSession). Improved handling of Unpersist – now updates AutoPlacement so that slot is reused when a new objects of the same type is persisted. Updated license check.


VelocityDB Version 4.0 Release Notes

28. December 2014 Mats (0)

Added untested versions of VelocityDB.dll for iOS and Android. The names of these added DLLs are: VelocityDBiOS.dll and VelocityDBAndroid.dll. They are part of the normal download, placed in installation folder. Do license check only when updating database schema. This enables deployment without a license database (4.odb). Updated User’s Guide describing this for deployments.

Issues with AllObjects<T> and UpdateTypeVersion

2. December 2014 ubique (0)

1) If I just call session.AllObjects<T> , I get an exception

Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information.
[ReflectionTypeLoadException: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information.]
   System.Reflection.RuntimeModule.GetTypes(RuntimeModule module) +0
   System.Reflection.RuntimeModule.GetTypes() +9
   System.Reflection.Assembly.GetTypes() +143
   VelocityDb.OfType.a(Assembly A_0) +14
   System.Linq.<SelectManyIterator>d__31`3.MoveNext() +267
   System.Linq.WhereSelectEnumerableIterator`2.MoveNext() +165
   VelocityDb.OfType.a(SessionBase A_0) +904
   VelocityDb.b.v() +1050
   VelocityDb.a.g() +221

But when I use session.AllObjects<T>(false), there is no such exception. I don't know is it a bug or not.


2) I need to update class with already persisted objects before after adding another indexable value (i.e.[Index]private string _anotherIndex ), but I cannot.

There is an exception (I've tried session.UpdateClass in different places)

Line 23:                 session.UpdateClass(typeof(DomainObject));
Line 24:                 foreach(var o in session.AllObjects<DomainObject>(false))
Line 25:                     o.UpdateTypeVersion();
Line 26:                 
Line 27:                 session.Commit();


Source File: --

Stack Trace: 

[ArgumentOutOfRangeException: Index and count must refer to a location within the buffer.
Parameter name: bytes]
   System.Text.UTF8Encoding.GetString(Byte[] bytes, Int32 index, Int32 count) +14309108
   VelocityDb.TypeInfo.DataMember.DecodeToString(Byte[] member, Int32& offset, Int32 numberOfBytes) +79
   VelocityDb.TypeInfo.DataMember.a(Byte[] A_0, Int32& A_1, Object A_2, IOptimizedPersistable A_3, SessionBase A_4, Page A_5, Boolean A_6, Schema A_7, Boolean A_8, List`1 A_9, Int32 A_10, Int32 A_11, Boolean A_12) +804
   VelocityDb.OptimizedPersistable.ReadMeUsingSchemaReflection(TypeVersion typeVersion, Byte[] memberBytes, Int32& offset, IOptimizedPersistable pObj, SessionBase session, Page page, Boolean useOidShort, Schema schema, Boolean openRefs, List`1 toLoadMembers, Int32 graphDepth, Int32 graphDepthToLoad, Boolean primitivesOnly) +481
   VelocityDb.TypeInfo.TypeVersion.LoadMembers(IOptimizedPersistable toLoad, Schema schema, List`1 toLoadMembers, Int32 graphDepth, Int32 graphDepthToLoad, SessionBase session, Boolean primitivesOnly) +372
   VelocityDb.TypeInfo.Schema.a(Byte[] A_0, Boolean A_1, SessionBase A_2, UInt64 A_3, Page A_4, Boolean A_5, List`1 A_6, Int32 A_7, Int32 A_8, TypeVersion A_9) +787
   VelocityDb.Page.Slot(UInt64 oid, Boolean openRefs, SessionBase session, Schema schema, Boolean iteration, List`1 toLoadMembers, Int32 graphDepth, Int32 graphDepthToLoad, TypeVersion shape) +801
   VelocityDb.Session.SessionBase.Open(UInt64 oid, Boolean update, List`1 toLoadMembers, Boolean inFlush, Int32 graphDepth, Int32 graphDepthToLoad, Boolean signalNotExistError) +648
   VelocityDb.Collection.BTree.BTreeSet`1.GetKey(Int32 index) +161
   VelocityDb.Collection.BTree.BTreeBase`2.binarySearch(Key aKey, Byte[] comparisonArrayIn, Boolean& isEqual) +668
   VelocityDb.Collection.BTree.BTreeBase`2.RemoveFromLeafRoot(Key key, Byte[] comparisonArray) +27
   VelocityDb.Collection.BTree.BTreeBase`2.Remove(Key key, Byte[] comparisonArray) +66
   VelocityDb.Session.SessionBase.deleteFromIndexes(IOptimizedPersistable pObjBeforeUpdates, TypeVersion typeVersion, TypeVersion objTypeVersion) +1134
   VelocityDb.Session.SessionBase.a(IOptimizedPersistable A_0) +155
   VelocityDb.Session.SessionBase.UpdateObject(IOptimizedPersistable obj, Boolean inFlush, Boolean deleteObjFromIndexes) +314
   VelocityDb.OptimizedPersistable.UpdateTypeVersion() +227

What do I do wrong?

Lazy using BTree collection

4. November 2014 ubique Question (0)

When I use BTreeSet<T> or BTreeMap<S,T> (where S is value type, T is OptimizedPersistable), how can I get just OID instead of full object? I.e. when using 

set.Where(x=>x.Id==1).First() 

or

map[id]

Sometimes I don't need to open full non-cached object from network and disk and I just want to get its oid (an element of internal keysArray or valuesArray). Is there any way to achieve it  ? Maybe is there some extension for this collections there?

Count of the objects per page

21. October 2014 ubique Question (1)

Would be performance affected if we store millions of frequently updated objects  with objectsPerPage = 1 (to avoid page locking for server session)? The storage is not considered