diff --git a/lib/datastore.js b/lib/datastore.js
index 5068397..5368249 100644
--- a/lib/datastore.js
+++ b/lib/datastore.js
@@ -61,6 +61,7 @@ Datastore.prototype.loadDatabase = function () {
  */
 Datastore.treatRawData = function (rawData) {
   var data = rawData.split('\n')
+    , dataById = {}
     , res = []
     , i;
 
@@ -69,11 +70,15 @@ Datastore.treatRawData = function (rawData) {
 
     try {
       doc = model.deserialize(data[i]);
-      if (doc._id) {res.push(doc); }
+      if (doc._id) { dataById[doc._id] = doc; }
     } catch (e) {
     }
   }
 
+  Object.keys(dataById).forEach(function (k) {
+    res.push(dataById[k]);
+  });
+
   return res;
 };
 
diff --git a/test/db.test.js b/test/db.test.js
index 7945b3d..66b10c9 100644
--- a/test/db.test.js
+++ b/test/db.test.js
@@ -36,7 +36,7 @@ describe('Database', function () {
   });
 
 
-  describe('Loading the database data from file', function () {
+  describe.only('Loading the database data from file', function () {
 
     it('Every line represents a document', function () {
       var now = new Date()
@@ -46,6 +46,7 @@ describe('Database', function () {
         , treatedData = Datastore.treatRawData(rawData)
         ;
 
+      treatedData.sort(function (a, b) { return a._id - b._id; });
       treatedData.length.should.equal(3);
       _.isEqual(treatedData[0], { _id: "1", a: 2, ages: [1, 5, 12] }).should.equal(true);
       _.isEqual(treatedData[1], { _id: "2", hello: 'world' }).should.equal(true);
@@ -60,6 +61,7 @@ describe('Database', function () {
         , treatedData = Datastore.treatRawData(rawData)
         ;
 
+      treatedData.sort(function (a, b) { return a._id - b._id; });
       treatedData.length.should.equal(2);
       _.isEqual(treatedData[0], { _id: "1", a: 2, ages: [1, 5, 12] }).should.equal(true);
       _.isEqual(treatedData[1], { _id: "3", nested: { today: now } }).should.equal(true);
@@ -73,11 +75,26 @@ describe('Database', function () {
         , treatedData = Datastore.treatRawData(rawData)
         ;
 
+      treatedData.sort(function (a, b) { return a._id - b._id; });
       treatedData.length.should.equal(2);
       _.isEqual(treatedData[0], { _id: "1", a: 2, ages: [1, 5, 12] }).should.equal(true);
       _.isEqual(treatedData[1], { _id: "2", hello: 'world' }).should.equal(true);
     });
 
+    it('If two lines concern the same doc (= same _id), the last one is the good version', function () {
+      var now = new Date()
+        , rawData = model.serialize({ _id: "1", a: 2, ages: [1, 5, 12] }) + '\n' +
+                    model.serialize({ _id: "2", hello: 'world' }) + '\n' +
+                    model.serialize({ _id: "1", nested: { today: now } })
+        , treatedData = Datastore.treatRawData(rawData)
+        ;
+
+      treatedData.sort(function (a, b) { return a._id - b._id; });
+      treatedData.length.should.equal(2);
+      _.isEqual(treatedData[0], { _id: "1", nested: { today: now } }).should.equal(true);
+      _.isEqual(treatedData[1], { _id: "2", hello: 'world' }).should.equal(true);
+    });
+
   });   // ==== End of 'Loading the database data from file' ==== //