If no filename is specified, an in-memory only datastore is created

lib/datastore.js

@@ -202,6 +202,9 @@ Datastore.prototype._loadDatabase = function (cb) {
     , self = this
     ;
 
+  // In-memory only datastore
+  if (!self.filename) { return callback(); }
+
   customUtils.ensureDirectoryExists(path.dirname(self.filename), function (err) {
     fs.exists(self.filename, function (exists) {
       if (!exists) {
@@ -302,6 +305,9 @@ Datastore.prototype.persistNewState = function (newDocs, cb) {
     , callback = cb || function () {}
     ;
 
+  // In-memory only datastore
+  if (!self.filename) { return callback(); }
+
   self.datafileSize += newDocs.length;
 
   newDocs.forEach(function (doc) {
@@ -519,5 +525,4 @@ Datastore.prototype.remove = function () {
 
 
 
-
 module.exports = Datastore;

package.json

@@ -1,6 +1,6 @@
 {
   "name": "nedb",
-  "version": "0.6.0",
+  "version": "0.6.1",
   "author": {
     "name": "tldr.io",
     "email": "hello@tldr.io"