StartTransaction

[victor Saquicela]

I have a problem with the code:

Friend Sub StartTransaction(ByVal reldb As _CRelationalDatabase)
        Dim x As DictionaryEntry
        Dim ce As CCacheEntry

        'precopy collection objects
        For Each x In Me
            ce = x.Value
            If ce.PersistentObject.GetClassMap.RelationalDatabase Is reldb Then
                ce.CopyObject()
            End If
        Next
    End Sub

I don't understand when ce.PersistentObject is nothing ?????????????

I am using transaction, when I execute my application and start a transaction, I create many objects without save, then execute rollback. It is correct, but now, if I start transaction inmediatily, i get an error.

Saludos

Victor

[victor Saquicela]

I am debuging this method, I think that when I create a new object into of the transaction and this object is add to cache, but I execute rollback, this object will be deleted, because when I init transaction and execute precopy collection objects, the cacheentry.persistent is false.

[Nobody/Anonymous]

any idea

[Richard Banks]

Sorry for not responding - I've been on holidays over Easter and haven't caught up yet.

Hopefully I'll get some time tomorrow to have a bit of a look at it.

[Richard Banks]

Hi Victor,

Sorry for the delay in getting back to you, it's been a very busy period...

I've just committed a number of changes to the framework that fixed a few issues with caching, etc.

Could you try your code against the new version, and if it still breaks could you put together an Nunit test that duplicates the problem for me - it will make it a lot easier to debug and prove that things work.

Thanks,
- Richard

[victor Saquicela]

Hi.

I have a same problem:

in the code:
Public Function Find(ByVal obj As IPersistableObject) As IPersistableObject
        Dim x As DictionaryEntry
        Dim ce As CCacheEntry
        Dim attrmap As CAttributeMap
        Dim i As Integer
        Dim found As Boolean
        Dim cm As CClassMap
        Dim t As Type
        Dim interval As Double

        cm = obj.GetClassMap

        'Debug.WriteLine("Cache - Attempt to Find() <" & cm.Name & "> object in cache")

        'We only process cache objects of the same type
        'We will check for cache expiry on the objects based on the time set in the
        'persistent object, or the cache default if not supplied.
        'Dirty objects cannot be deleted from the cache.

        Dim m_Enumerator As Collections.IEnumerator = Me.GetEnumerator()

        While m_Enumerator.MoveNext()
            x = m_Enumerator.Current
            ce = x.Value
            t = ce.PersistentObject.GetObjectType
            If t Is obj.GetObjectType Or t.IsSubclassOf(obj.GetObjectType) Then
                If ce.IsExpired() And Not ce.PersistentObject.IsDirty Then
                    'Debug.WriteLine("Cache - Removing expired object from cache during Find()")
                    MyBase.Remove(x.Key)                     'delete object from cache
                    m_Enumerator = Me.GetEnumerator
                    m_Enumerator.Reset()                    'Reset enumerator after removing item
                Else
                    found = True
                    For i = 1 To cm.getFindSize
                        attrmap = cm.FindAttributeMaps(i)
                        If obj.GetValueByAttribute(attrmap.Name) <> ce.PersistentObject.GetValueByAttribute(attrmap.Name) Then
                            found = False
                            Exit For
                        End If
                    Next i
                    If found Then
                        'Debug.WriteLine("Cache - Found object in cache")
                        If ce.TransactionType = CCacheEntry.CacheTransaction.Deleted Then
                            m_status = StatusEnum.Deleted
                            Return Nothing
                        End If
                        Debug.WriteLine([String].Format("Cache - getting {0} object from cache.  Key..." & vbCrLf & x.Key.ToString, x.Key.ObjType.Name))
                        m_status = StatusEnum.Found
                        Return GetCachedObject(ce)
                    End If
                End If
            End If
        End While
        'Debug.WriteLine("Cache - object not cached")
        m_status = StatusEnum.NotFound
        Return Nothing
    End Function

*****************************
in the line
t = ce.PersistentObject.GetObjectType

ce.PersistentObject is nothing, then error is produced. I don't understand because only an object is the problem.

my code is:
begin transaction

serial.nombre="a"
serial.find(serial)
serial.valor=serial.valor+1
serial.save

...... .....

rollback

.....

an any object

a.find(a)

when the atoms find a in the cache, the object serial have a property PersistenObject is nothing int he cacheEntry.

Why??????????? or I am doing bad

[Richard Banks]

Hi Victor,

It's very hard to tell what's going on from here.

It's probably a bug in the cache rollback code, but I've got a number of NUnit tests that check for cache problems after a rollback and they all pass.

It would _really_ help if you could take the Nunit code from CVS, add a test that duplicates the problem and send me the code, or post it as a patch.  If you need to add a table to the Original Db1.mdb file it's not a problem, as I'll keep your test in the test suite to make sure I don't break the code in future changes.

- Richard