         
         if aObj.uid {
             self.cache.removeObjectForKey(aObj.uid!)
-            self.deleteData(aObj.uid!)
+            self.deleteBlock(aObj.uid!)
             aObj.uid = nil;
         }
     }

        if !aObj.uid {
            // only NEW object have a nil uid
            
            var pos  = self.register()
            result = self.calculateID(pos)
            aObj.uid = result
            

            // store SampleData as ID:0 in the file
            // ID:0 is a reserved ID and should not be availabled for public access
            var header = ObjectStoreHeader(used: false)
            self.writeHeader(header)
            
            let sampleData = O()
            self.writeData(sampleData.data)
            
        } else {
            let pos = calculatePos(1)
