diff --git a/lib/connector.js b/lib/connector.js
index efb3843d..9372ef6d 100644
--- a/lib/connector.js
+++ b/lib/connector.js
@@ -17,6 +17,22 @@ function Connector(name, settings) {
  */
 Connector.prototype.relational = false;
 
+/*!
+ * Get the connector type/subtype
+ * @returns {String} The type for the connector
+ */
+Connector.prototype.getType = function() {
+  return 'db/nosql';
+};
+
+/**
+ * Get the default data type for ID
+ * @returns {Function} The default type for ID
+ */
+Connector.prototype.getDefaultIdType = function() {
+  return String;
+};
+
 /**
  * Execute a command with given parameters
  * @param {String} command The command such as SQL
diff --git a/lib/connectors/memory.js b/lib/connectors/memory.js
index 7c337d43..29e6dd8e 100644
--- a/lib/connectors/memory.js
+++ b/lib/connectors/memory.js
@@ -35,6 +35,14 @@ function Memory(m, settings) {
 
 util.inherits(Memory, Connector);
 
+Memory.prototype.getDefaultIdType = function() {
+  return Number;
+};
+
+Memory.prototype.getType = function() {
+  return 'db/nosql/memory';
+};
+
 Memory.prototype.connect = function (callback) {
   if (this.isTransaction) {
     this.onTransactionExec = callback;
diff --git a/lib/datasource.js b/lib/datasource.js
index 8f11368c..c035b23b 100644
--- a/lib/datasource.js
+++ b/lib/datasource.js
@@ -424,17 +424,27 @@ DataSource.prototype.defineRelations = function (modelClass, relations) {
 
 /*!
  * Set up the data access functions from the data source
- * @param modelClass
- * @param settings
+ * @param {Model} modelClass The model class
+ * @param {Object} settings The settings object
  */
 DataSource.prototype.setupDataAccess = function (modelClass, settings) {
-  if (this.connector && this.connector.define) {
-    // pass control to connector
-    this.connector.define({
-      model: modelClass,
-      properties: modelClass.definition.properties,
-      settings: settings
-    });
+  if (this.connector) {
+    // Check if the id property should be generated
+    var idName = modelClass.definition.idName();
+    var idProp = modelClass.definition.properties[idName];
+    if(idProp && idProp.generated && this.connector.getDefaultIdType) {
+      // Set the default id type from connector's ability
+      var idType = this.connector.getDefaultIdType() || String;
+      idProp.type = idType;
+    }
+    if (this.connector.define) {
+      // pass control to connector
+      this.connector.define({
+        model: modelClass,
+        properties: modelClass.definition.properties,
+        settings: settings
+      });
+    }
   }
 
   // add data access objects
@@ -567,6 +577,14 @@ DataSource.prototype.getModelDefinition = function (name) {
   return this.modelBuilder.getModelDefinition(name);
 };
 
+/**
+ * Get the data source type
+ * @returns {String} The data source type, such as db/relational, db/nosql, rest
+ */
+DataSource.prototype.getType = function() {
+  return this.connector && this.connector.getType();
+};
+
 /**
  * Attach an existing model to a data source.
  *
diff --git a/lib/sql.js b/lib/sql.js
index b3b5c664..06e33dc5 100644
--- a/lib/sql.js
+++ b/lib/sql.js
@@ -19,6 +19,22 @@ util.inherits(BaseSQL, Connector);
  */
 BaseSQL.prototype.relational = true;
 
+/*!
+ * Get the connector type/subtype
+ * @returns {string}
+ */
+BaseSQL.prototype.getType = function() {
+  return 'db/relational';
+};
+
+/*!
+ * Get the default data type for ID
+ * @returns {Function}
+ */
+BaseSQL.prototype.getDefaultIdType = function() {
+  return Number;
+};
+
 BaseSQL.prototype.query = function () {
   throw new Error('query method should be declared in connector');
 };
diff --git a/test/loopback-dl.test.js b/test/loopback-dl.test.js
index 205ee4e1..49ac88ab 100644
--- a/test/loopback-dl.test.js
+++ b/test/loopback-dl.test.js
@@ -416,6 +416,40 @@ describe('DataSource define model', function () {
     });
   });
 
+  it('injects id by default', function (done) {
+    var ds = new ModelBuilder();
+
+    var User = ds.define('User', {});
+    assert.deepEqual(User.definition.properties.id,
+      {type: Number, id: 1, generated: true});
+
+    done();
+  });
+
+  it('disables idInjection if the value is false', function (done) {
+    var ds = new ModelBuilder();
+
+    var User1 = ds.define('User', {}, {idInjection: false});
+    assert(!User1.definition.properties.id);
+    done();
+  });
+
+  it('updates generated id type by the connector', function (done) {
+    var builder = new ModelBuilder();
+
+    var User = builder.define('User', {id: {type: String, generated: true, id: true}});
+    assert.deepEqual(User.definition.properties.id,
+      {type: String, id: 1, generated: true});
+
+    var ds = new DataSource('memory');// define models
+    User.attachTo(ds);
+
+    assert.deepEqual(User.definition.properties.id,
+      {type: Number, id: 1, generated: true});
+
+    done();
+  });
+
 });
 
 describe('Load models with base', function () {