diff --git a/benchmarks/findOne.js b/benchmarks/findOne.js
index d5248e1..64ec3d9 100644
--- a/benchmarks/findOne.js
+++ b/benchmarks/findOne.js
@@ -7,15 +7,30 @@ var Datastore = require('../lib/datastore')
   , execTime = require('exec-time')
   , profiler = new execTime('FINDONE BENCH')
   , d = new Datastore(benchDb)
-  , n = 10000
+  , program = require('commander')
+  , n
   ;
 
-if (process.argv[2]) { n = parseInt(process.argv[2], 10); }
+program
+  .option('-n --number [number]', 'Size of the collection to test on', parseInt)
+  .option('-i --with-index', 'Test with an index')
+  .parse(process.argv);
+
+n = program.number || 10000;
+
+console.log("----------------------------");
+console.log("Test with " + n + " documents");
+console.log(program.withIndex ? "Use an index" : "Don't use an index");
+console.log("----------------------------");
 
 async.waterfall([
   async.apply(commonUtilities.prepareDb, benchDb)
 , function (cb) {
-    d.loadDatabase(cb);
+    d.loadDatabase(function (err) {
+      if (err) { return cb(err); }
+      if (program.withIndex) { d.ensureIndex({ fieldName: 'docNumber' }); }
+      cb();
+    });
   }
 , function (cb) { profiler.beginProfiling(); return cb(); }
 , async.apply(commonUtilities.insertDocs, d, n, profiler)
diff --git a/lib/datastore.js b/lib/datastore.js
index 0814f6e..c2188b0 100644
--- a/lib/datastore.js
+++ b/lib/datastore.js
@@ -65,6 +65,30 @@ Datastore.prototype.addToIndexes = function (doc) {
 };
 
 
+/**
+ * Remove one or several document(s) from all indexes
+ */
+Datastore.prototype.removeFromIndexes = function (doc) {
+  var self = this;
+
+  Object.keys(this.indexes).forEach(function (i) {
+    self.indexes[i].remove(doc);
+  });
+};
+
+
+/**
+ * Update a document in all indexes
+ */
+Datastore.prototype.removeFromIndexes = function (doc, newDoc) {
+  var self = this;
+
+  Object.keys(this.indexes).forEach(function (i) {
+    self.indexes[i].update(doc, newDoc);
+  });
+};
+
+
 /**
  * Return the list of candidates for a given query
  * Very crude implementation for now, we return the candidates given by the first usable index if any
@@ -254,13 +278,14 @@ Datastore.prototype.find = function (query, callback) {
  */
 Datastore.prototype.findOne = function (query, callback) {
   var self = this
+    , candidates = this.getCandidates(query)
     , i
     ;
 
   try {
-    for (i = 0; i < self.data.length; i += 1) {
-      if (model.match(self.data[i], query)) {
-        return callback(null, model.deepCopy(self.data[i]));
+    for (i = 0; i < candidates.length; i += 1) {
+      if (model.match(candidates[i], query)) {
+        return callback(null, model.deepCopy(candidates[i]));
       }
     }
   } catch (err) {