--- a/dlight.management/src/org/netbeans/modules/dlight/management/api/impl/DataStorageManager.java	
+++ a/dlight.management/src/org/netbeans/modules/dlight/management/api/impl/DataStorageManager.java	
@@ -43,6 +43,7 @@ 
 
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -141,10 +142,25 @@ 
      *  for requested schema (if it can be found within all available DataStorages)
      */
     public synchronized  Map<DataStorageType, DataStorage> getDataStoragesFor(DLightSession session, DataCollector<?> collector) {
+        if (session == null || collector == null) {
+            return Collections.<DataStorageType, DataStorage>emptyMap();
+        }
+        
         Map<DataStorageType, DataStorage> result = new HashMap<DataStorageType, DataStorage>();
+        
         for (DataStorageType type : collector.getRequiredDataStorageTypes()) {
-            result.put(type, getDataStorageFor(session, type, collector.getDataTablesMetadata()));
+            final DataStorage dataStorage = getDataStorageFor(session, type, collector.getDataTablesMetadata());
+            
+            if (dataStorage != null) {
+                result.put(type, dataStorage);
+            } else {
+                DLightLogger.getLogger(DataStorageManager.class).log(Level.INFO,
+                        "DataStorageManager.getDataStoragesFor(DLightSession, DataCollector<?>):" // NOI18N
+                        + " NULL storage returned for type={0} [session={1}, collector={2}]", // NOI18N
+                        new Object[] {type, session.getDisplayName(), collector.getName()});
+            }
         }
+        
         return result;
     }
 
@@ -484,9 +500,16 @@ 
                 DataStorage newStorage = storage.createStorage();
                 if (newStorage instanceof ProxyDataStorage) {
                     ProxyDataStorage proxyStorage = (ProxyDataStorage) newStorage;
-                    DataStorage backendStorage = getDataStorageFor(session, proxyStorage.getBackendDataStorageType(), proxyStorage.getBackendTablesMetadata());
+                    DataStorageType requiredStorageType = proxyStorage.getBackendDataStorageType();
+                    List<DataTableMetadata> requiredTables = proxyStorage.getBackendTablesMetadata();
+                    DataStorage backendStorage = getDataStorageFor(session, requiredStorageType, requiredTables);
+                    if (backendStorage == null) {
+                        // Means that required (for this proxy) storage cannot be found ...
+                        continue;
+                    }
                     proxyStorage.attachTo(backendStorage);
                 }
+                
                 if (newStorage != null) {
                     newStorage.createTables(tableMetadatas);
                     if (activeSessionStorages == null) {
@@ -507,9 +530,15 @@ 
                     if (newStorage != null) {
                         if (newStorage instanceof ProxyDataStorage) {
                             ProxyDataStorage proxyStorage = (ProxyDataStorage) newStorage;
-                            DataStorage backendStorage = getDataStorageFor(session, proxyStorage.getBackendDataStorageType(), proxyStorage.getBackendTablesMetadata());
+                            DataStorageType requiredStorageType = proxyStorage.getBackendDataStorageType();
+                            List<DataTableMetadata> requiredTables = proxyStorage.getBackendTablesMetadata();
+                            DataStorage backendStorage = getDataStorageFor(session, requiredStorageType, requiredTables);
+                            if (backendStorage == null) {
+                                continue;
+                            }
                             proxyStorage.attachTo(backendStorage);
                         }
+                        
                         newStorage.createTables(tableMetadatas);
 
                         return newStorage;