diff --git a/packages/loki/src/collection.ts b/packages/loki/src/collection.ts
index 016b7ce4..fd187e4e 100644
--- a/packages/loki/src/collection.ts
+++ b/packages/loki/src/collection.ts
@@ -307,48 +307,73 @@ export class Collection<TData extends object = object, TNested extends object =
   toJSON(): Collection.Serialized {
     return {
       name: this.name,
-      unindexedSortComparator: this._unindexedSortComparator,
-      defaultLokiOperatorPackage: this._defaultLokiOperatorPackage,
+      _unindexedSortComparator: this._unindexedSortComparator,
+      _defaultLokiOperatorPackage: this._defaultLokiOperatorPackage,
       _dynamicViews: this._dynamicViews,
-      uniqueNames: Object.keys(this._constraints.unique),
-      transforms: this._transforms as any,
-      rangedIndexes: this._rangedIndexes as any,
+      _uniqueNames: Object.keys(this._constraints.unique),
+      _transforms: this._transforms as any,
+      _rangedIndexes: this._rangedIndexes as any,
       _data: this._data,
-      idIndex: this._idIndex,
-      maxId: this._maxId,
+      _idIndex: this._idIndex,
+      _maxId: this._maxId,
       _dirty: this._dirty,
       _nestedProperties: this._nestedProperties,
-      transactional: this._transactional,
-      asyncListeners: this._asyncListeners,
-      disableMeta: this._disableMeta,
-      disableChangesApi: this._disableChangesApi,
-      disableDeltaChangesApi: this._disableDeltaChangesApi,
-      cloneObjects: this._cloneObjects,
-      cloneMethod: this._cloneMethod,
-      changes: this._changes,
+      _transactional: this._transactional,
+      _asyncListeners: this._asyncListeners,
+      _disableMeta: this._disableMeta,
+      _disableChangesApi: this._disableChangesApi,
+      _disableDeltaChangesApi: this._disableDeltaChangesApi,
+      _cloneObjects: this._cloneObjects,
+      _cloneMethod: this._cloneMethod,
+      _changes: this._changes,
       _fullTextSearch: this._fullTextSearch
     };
   }
 
-  static fromJSONObject(obj: Collection.Serialized, options?: Collection.DeserializeOptions) {
+  static migrate(obj: Collection.Serialized /*| Collection */, migrateFromVersion: string) {
+    if (!migrateFromVersion) {
+      return;
+    }
+    if (migrateFromVersion === 1.5) {
+      let src = obj as any as Collection.Serialized_1_5;
+      obj._unindexedSortComparator = src.unindexedSortComparator;
+      obj._defaultLokiOperatorPackage = src.defaultLokiOperatorPackage;
+      obj._uniqueNames = src.uniqueNames;
+      obj._transforms = src.transforms;
+      obj._rangedIndexes = src.rangedIndexes;
+      obj._idIndex = src.idIndex;
+      obj._maxId = src.maxId;
+      obj._transactional = src.transactional;
+      obj._asyncListeners = src.asyncListeners;
+      obj._disableMeta = src.disableMeta;
+      obj._disableChangesApi = src.disableChangesApi;
+      obj._disableDeltaChangesApi = src.disableDeltaChangesApi;
+      obj._cloneObjects = src.cloneObjects;
+      obj._cloneMethod = src.cloneMethod;
+      obj._changes = src.changes;
+    }
+  }
+
+  static fromJSONObject(obj: Collection.Serialized /*| Collection */, options?: Collection.DeserializeOptions, migrateFromVersion?: string) {
+    Collection.migrate(obj, migrateFromVersion);
+
     // instantiate collection with options needed by constructor
     let coll = new Collection<any>(obj.name, {
-      disableChangesApi: obj.disableChangesApi,
-      disableDeltaChangesApi: obj.disableDeltaChangesApi,
-      unindexedSortComparator: obj.unindexedSortComparator,
-      defaultLokiOperatorPackage: obj.defaultLokiOperatorPackage
+      disableChangesApi: obj._disableChangesApi,
+      disableDeltaChangesApi: obj._disableDeltaChangesApi,
+      unindexedSortComparator: obj._unindexedSortComparator,
+      defaultLokiOperatorPackage: obj._defaultLokiOperatorPackage
     });
 
-    coll._transactional = obj.transactional;
-    coll._asyncListeners = obj.asyncListeners;
-    coll._disableMeta = obj.disableMeta;
-    coll._disableChangesApi = obj.disableChangesApi;
-    coll._cloneObjects = obj.cloneObjects;
-    coll._cloneMethod = obj.cloneMethod || "deep";
-    coll._changes = obj.changes;
+    coll._transactional = obj._transactional;
+    coll._asyncListeners = obj._asyncListeners;
+    coll._disableMeta = obj._disableMeta;
+    coll._disableChangesApi = obj._disableChangesApi;
+    coll._cloneObjects = obj._cloneObjects;
+    coll._cloneMethod = obj._cloneMethod || "deep";
+    coll._changes = obj._changes;
     coll._nestedProperties = obj._nestedProperties as any[];
-    coll._rangedIndexes = obj.rangedIndexes || {};
-
+    coll._rangedIndexes = obj._rangedIndexes || {};
     coll._dirty = (options && options.retainDirtyFlags === true) ? obj._dirty : false;
 
     function makeLoader(coll: Collection.Serialized) {
@@ -388,16 +413,16 @@ export class Collection<TData extends object = object, TNested extends object =
       }
     }
 
-    coll._maxId = (obj.maxId === undefined) ? 0 : obj.maxId;
-    coll._idIndex = obj.idIndex;
-    if (obj.transforms !== undefined) {
-      coll._transforms = obj.transforms;
+    coll._maxId = (obj._maxId === undefined) ? 0 : obj._maxId;
+    coll._idIndex = obj._idIndex;
+    if (obj._transforms !== undefined) {
+      coll._transforms = obj._transforms;
     }
 
     // inflate rangedindexes
-    for (let ri in obj.rangedIndexes) {
+    for (let ri in obj._rangedIndexes) {
       // shortcut reference to serialized meta
-      let sri = obj.rangedIndexes[ri];
+      let sri = obj._rangedIndexes[ri];
       // lookup index factory function in map based on index type name
       let rif = RangedIndexFactoryMap[sri.indexTypeName];
       // lookup comparator function in map based on comparator name
@@ -413,9 +438,15 @@ export class Collection<TData extends object = object, TNested extends object =
     coll._ensureId();
 
     // regenerate unique indexes
-    if (obj.uniqueNames !== undefined) {
-      for (let j = 0; j < obj.uniqueNames.length; j++) {
-        coll.ensureUniqueIndex(obj.uniqueNames[j]);
+    let uniqueNames = obj._uniqueNames;
+    // Check if type is collection.
+    let maybeColl = obj as any as Collection<any>;
+    if (maybeColl._constraints && maybeColl._constraints.unique !== undefined) {
+      uniqueNames = Object.keys(maybeColl._constraints.unique);
+    }
+    if (uniqueNames) {
+      for (let j = 0; j < uniqueNames.length; j++) {
+        coll.ensureUniqueIndex(uniqueNames[j]);
       }
     }
 
@@ -1709,6 +1740,30 @@ export namespace Collection {
   }
 
   export interface Serialized {
+    name: string;
+    _unindexedSortComparator: string;
+    _defaultLokiOperatorPackage: string;
+    _dynamicViews: DynamicView[];
+    _nestedProperties: { name: string, path: string[] }[];
+    _uniqueNames: string[];
+    _transforms: Dict<Transform[]>;
+    _rangedIndexes: RangedIndexOptions;
+    _data: Doc<any>[];
+    _idIndex: number[];
+    _maxId: number;
+    _dirty: boolean;
+    _transactional: boolean;
+    _asyncListeners: boolean;
+    _disableMeta: boolean;
+    _disableChangesApi: boolean;
+    _disableDeltaChangesApi: boolean;
+    _cloneObjects: boolean;
+    _cloneMethod: CloneMethod;
+    _changes: any;
+    _fullTextSearch: FullTextSearch;
+  }
+
+  export interface Serialized_1_5 {
     name: string;
     unindexedSortComparator: string;
     defaultLokiOperatorPackage: string;
diff --git a/packages/loki/src/loki.ts b/packages/loki/src/loki.ts
index 8b636c7e..349498f4 100644
--- a/packages/loki/src/loki.ts
+++ b/packages/loki/src/loki.ts
@@ -39,8 +39,8 @@ export class Loki extends LokiEventEmitter {
 
   // persist version of code which created the database to the database.
   // could use for upgrade scenarios
-  private databaseVersion: number = 1.5; // TODO
-  private engineVersion: number = 1.5;
+  private databaseVersion: number = 1.6;
+  private engineVersion: number = 1.6;
 
   public _collections: Collection[];
 
@@ -171,7 +171,7 @@ export class Loki extends LokiEventEmitter {
     };
 
     // process the options
-    if (this._persistenceMethod !== undefined) {
+    if (options.persistenceMethod && options.persistenceMethod !== "adapter") {
       // check if the specified persistence method is known
       if (typeof(PERSISTENCE_METHODS[this._persistenceMethod]) === "function") {
         this._persistenceAdapter = new (PERSISTENCE_METHODS[this._persistenceMethod]);
@@ -707,16 +707,15 @@ export class Loki extends LokiEventEmitter {
    * @param {object} options - apply or override collection level settings
    * @param {boolean} options.retainDirtyFlags - whether collection dirty flags will be preserved
    */
-  public loadJSONObject(dbObject: Loki, options?: Collection.DeserializeOptions): void;
-  public loadJSONObject(dbObject: Loki.Serialized, options?: Collection.DeserializeOptions): void;
-  public loadJSONObject(dbObject: any, options: Collection.DeserializeOptions = {}): void {
+  public loadJSONObject(dbObject: Loki | Loki.Serialized, options?: Collection.DeserializeOptions): void {
     const len = dbObject._collections ? dbObject._collections.length : 0;
 
     this.filename = dbObject.filename;
     this._collections = [];
 
     for (let i = 0; i < len; ++i) {
-      this._collections.push(Collection.fromJSONObject(dbObject._collections[i], options));
+      const migrateFromVersion = (dbObject as any).databaseVersion == this.databaseVersion ? "" : (dbObject as any).databaseVersion;
+      this._collections.push(Collection.fromJSONObject(dbObject._collections[i] as any, options, migrateFromVersion));
     }
   }
 
diff --git a/packages/partitioning-adapter/spec/generic/partitioning.spec.ts b/packages/partitioning-adapter/spec/generic/partitioning.spec.ts
index 5b9333dd..3820ff02 100644
--- a/packages/partitioning-adapter/spec/generic/partitioning.spec.ts
+++ b/packages/partitioning-adapter/spec/generic/partitioning.spec.ts
@@ -74,6 +74,9 @@ describe("partitioning adapter", () => {
       expect(db2["_collections"][1].count()).toEqual(1);
       expect(db2.getCollection<User>("items").findOne({name: "gungnir"}).owner).toEqual("odin");
       expect(db2.getCollection<AB>("another").findOne({a: 1}).b).toEqual(3);
+      // Insert still works.
+      db2.getCollection<AB>("another").insert({a: 2, b: 4});
+      expect(db2.getCollection<AB>("another").findOne({a: 2}).b).toEqual(4);
     }).then(done, done.fail);
   });