diff --git a/lib/datastore.js b/lib/datastore.js
index 7141648..7ab3163 100644
--- a/lib/datastore.js
+++ b/lib/datastore.js
@@ -2,7 +2,9 @@
  * The datastore itself
  * TODO
  * Improve serialization (for types such as Dates, handle new lines in strings)
+ * Serialization and deserialization functions
  * Queue inserts, removes and updates
+ * Update and removes should only modify the corresponding part of the database
  */
 
 var fs = require('fs')
@@ -180,14 +182,32 @@ Datastore.prototype.persistWholeDatabase = function (data, cb) {
 
 
 /**
- * Update the first doc matching query
+ * Update all docs matching query
+ * For now, very naive implementation (recalculating the whole database)
  * @param {Object} query
- * @param {Object} newDoc Will replace the former doc
- * @param {Function} cb Optional callback, signature: err, replaced?, newDoc
+ * @param {Object} newDoc Will replace the former docs
+ * @param {Function} cb Optional callback, signature: err, numReplaced
  */
-Datastore.prototype.updateOne = function (query, newDoc, cb) {
-  var callback = cb || function () {};
+Datastore.prototype.update = function (query, newDoc, cb) {
+  var callback = cb || function () {}
+    , self = this
+    , numReplaced = 0
+    , newData = [];
+
+  self.data.forEach(function (d) {
+    if (Datastore.match(d, query)) {
+      numReplaced += 1;
+      newData.push(newDoc);
+    } else {
+      newData.push(d);
+    }
+  });
 
+  self.persistWholeDatabase(newData, function (err) {
+    if (err) { return callback(err); }
+    self.data = newData;
+    return callback(null, numReplaced);
+  });
 };
 
 
@@ -196,8 +216,12 @@ Datastore.prototype.updateOne = function (query, newDoc, cb) {
 var d = new Datastore('workspace/test.db');
 d.loadDatabase(function (err) {
   console.log(d.data);
-  d.data = [{ff: 'mec'}, {ee: 'test'}];
 
+  d.update({ yahoo: 'dailymotion' }, {yahoo: 'great' }, function (err, n) {
+    console.log("--------------");
+    console.log(err);
+    console.log(n);
+  });
 
 });