diff --git a/src/application/migrations/009_change_column_types.php b/src/application/migrations/009_change_column_types.php
new file mode 100644
index 00000000..7748247a
--- /dev/null
+++ b/src/application/migrations/009_change_column_types.php
@@ -0,0 +1,364 @@
+<?php defined('BASEPATH') OR exit('No direct script access allowed');
+
+/* ----------------------------------------------------------------------------
+ * Easy!Appointments - Open Source Web Scheduler
+ *
+ * @package     EasyAppointments
+ * @author      A.Tselegidis <alextselegidis@gmail.com>
+ * @copyright   Copyright (c) 2013 - 2017, Alex Tselegidis
+ * @license     http://opensource.org/licenses/GPL-3.0 - GPLv3
+ * @link        http://easyappointments.org
+ * @since       v1.3.0
+ * ---------------------------------------------------------------------------- */
+
+class Migration_Change_column_types extends CI_Migration {
+    public function up()
+    {
+        $this->load->dbforge();
+
+        // Appointments
+        $fields = [
+            'id' => [
+                'name' => 'id',
+                'type' => 'int',
+                'constraint' => '11',
+                'auto_increment' => TRUE
+            ],
+            'id_users_provider' => [
+                'name' => 'id_users_provider',
+                'type' => 'int',
+                'constraint' => '11'
+            ],
+            'id_users_customer' => [
+                'name' => 'id_users_customer',
+                'type' => 'int',
+                'constraint' => '11'
+            ],
+            'id_services' => [
+                'name' => 'id_services',
+                'type' => 'int',
+                'constraint' => '11'
+            ]
+        ];
+
+        $this->dbforge->modify_column('ea_appointments', $fields);
+
+        // Roles
+        $fields = [
+            'id' => [
+                'name' => 'id',
+                'type' => 'int',
+                'constraint' => '11',
+                'auto_increment' => TRUE
+            ],
+            'appointments' => [
+                'name' => 'appointments',
+                'type' => 'int',
+                'constraint' => '11'
+            ],
+            'customers' => [
+                'name' => 'customers',
+                'type' => 'int',
+                'constraint' => '11'
+            ],
+            'services' => [
+                'name' => 'services',
+                'type' => 'int',
+                'constraint' => '11'
+            ],
+            'users' => [
+                'name' => 'users',
+                'type' => 'int',
+                'constraint' => '11'
+            ],
+            'system_settings' => [
+                'name' => 'system_settings',
+                'type' => 'int',
+                'constraint' => '11'
+            ],
+            'user_settings' => [
+                'name' => 'user_settings',
+                'type' => 'int',
+                'constraint' => '11'
+            ]
+        ];
+
+        $this->dbforge->modify_column('ea_roles', $fields);
+
+        // Secretary Provider
+        $fields = [
+            'id_users_secretary' => [
+                'name' => 'id_users_secretary',
+                'type' => 'int',
+                'constraint' => '11'
+            ],
+            'id_users_provider' => [
+                'name' => 'id_users_provider',
+                'type' => 'int',
+                'constraint' => '11'
+            ]
+        ];
+
+        $this->dbforge->modify_column('ea_roles', $fields);
+
+        // Services
+        $fields = [
+            'id' => [
+                'name' => 'id',
+                'type' => 'int',
+                'constraint' => '11',
+                'auto_increment' => TRUE
+            ],
+            'id_service_categories' => [
+                'name' => 'id_service_categories',
+                'type' => 'int',
+                'constraint' => '11'
+            ]
+        ];
+
+        $this->dbforge->modify_column('ea_services', $fields);
+
+        // Service Providers
+        $fields = [
+            'id_users' => [
+                'name' => 'id_users',
+                'type' => 'int',
+                'constraint' => '11'
+            ],
+            'id_services' => [
+                'name' => 'id_services',
+                'type' => 'int',
+                'constraint' => '11'
+            ]
+        ];
+
+        $this->dbforge->modify_column('ea_services_providers', $fields);
+
+        // Service Categories
+        $fields = [
+            'id' => [
+                'name' => 'id',
+                'type' => 'int',
+                'constraint' => '11',
+                'auto_increment' => TRUE
+            ]
+        ];
+
+        $this->dbforge->modify_column('ea_service_categories', $fields);
+
+        // Settings
+        $fields = [
+            'id' => [
+                'name' => 'id',
+                'type' => 'int',
+                'constraint' => '11',
+                'auto_increment' => TRUE
+            ]
+        ];
+
+        $this->dbforge->modify_column('ea_settings', $fields);
+
+        // Users
+        $fields = [
+            'id' => [
+                'name' => 'id',
+                'type' => 'int',
+                'constraint' => '11',
+                'auto_increment' => TRUE
+            ],
+            'id_roles' => [
+                'name' => 'id',
+                'type' => 'int',
+                'constraint' => '11'
+            ]
+        ];
+
+        $this->dbforge->modify_column('ea_users', $fields);
+
+        // Users Settings
+        $fields = [
+            'id_users' => [
+                'name' => 'id_users',
+                'type' => 'int',
+                'constraint' => '11'
+            ]
+        ];
+
+        $this->dbforge->modify_column('ea_user_settings', $fields);
+    }
+
+    public function down()
+    {
+        $this->load->dbforge();
+
+        // Appointments
+        $fields = [
+            'id' => [
+                'name' => 'id',
+                'type' => 'bigint',
+                'constraint' => '20',
+                'auto_increment' => TRUE
+            ],
+            'id_users_provider' => [
+                'name' => 'id_users_provider',
+                'type' => 'bigint',
+                'constraint' => '20'
+            ],
+            'id_users_customer' => [
+                'name' => 'id_users_customer',
+                'type' => 'bigint',
+                'constraint' => '20'
+            ],
+            'id_services' => [
+                'name' => 'id_services',
+                'type' => 'bigint',
+                'constraint' => '20'
+            ]
+        ];
+
+        $this->dbforge->modify_column('ea_appointments', $fields);
+
+        // Roles
+        $fields = [
+            'id' => [
+                'name' => 'id',
+                'type' => 'bigint',
+                'constraint' => '20',
+                'auto_increment' => TRUE
+            ],
+            'appointments' => [
+                'name' => 'appointments',
+                'type' => 'bigint',
+                'constraint' => '20'
+            ],
+            'customers' => [
+                'name' => 'customers',
+                'type' => 'bigint',
+                'constraint' => '20'
+            ],
+            'services' => [
+                'name' => 'services',
+                'type' => 'bigint',
+                'constraint' => '20'
+            ],
+            'users' => [
+                'name' => 'users',
+                'type' => 'bigint',
+                'constraint' => '20'
+            ],
+            'system_settings' => [
+                'name' => 'system_settings',
+                'type' => 'bigint',
+                'constraint' => '20'
+            ],
+            'user_settings' => [
+                'name' => 'user_settings',
+                'type' => 'bigint',
+                'constraint' => '20'
+            ]
+        ];
+
+        $this->dbforge->modify_column('ea_roles', $fields);
+
+        // Secretary Provider
+        $fields = [
+            'id_users_secretary' => [
+                'name' => 'id_users_secretary',
+                'type' => 'bigint',
+                'constraint' => '20'
+            ],
+            'id_users_provider' => [
+                'name' => 'id_users_provider',
+                'type' => 'bigint',
+                'constraint' => '20'
+            ]
+        ];
+
+        $this->dbforge->modify_column('ea_roles', $fields);
+
+        // Services
+        $fields = [
+            'id' => [
+                'name' => 'id',
+                'type' => 'bigint',
+                'constraint' => '20',
+                'auto_increment' => TRUE
+            ],
+            'id_service_categories' => [
+                'name' => 'id_service_categories',
+                'type' => 'bigint',
+                'constraint' => '20'
+            ]
+        ];
+
+        $this->dbforge->modify_column('ea_services', $fields);
+
+        // Service Providers
+        $fields = [
+            'id_users' => [
+                'name' => 'id_users',
+                'type' => 'bigint',
+                'constraint' => '20'
+            ],
+            'id_services' => [
+                'name' => 'id_services',
+                'type' => 'bigint',
+                'constraint' => '20'
+            ]
+        ];
+
+        $this->dbforge->modify_column('ea_services_providers', $fields);
+
+        // Service Categories
+        $fields = [
+            'id' => [
+                'name' => 'id',
+                'type' => 'bigint',
+                'constraint' => '20',
+                'auto_increment' => TRUE
+            ]
+        ];
+
+        $this->dbforge->modify_column('ea_service_categories', $fields);
+
+        // Settings
+        $fields = [
+            'id' => [
+                'name' => 'id',
+                'type' => 'bigint',
+                'constraint' => '20',
+                'auto_increment' => TRUE
+            ]
+        ];
+
+        $this->dbforge->modify_column('ea_settings', $fields);
+
+        // Users
+        $fields = [
+            'id' => [
+                'name' => 'id',
+                'type' => 'bigint',
+                'constraint' => '20',
+                'auto_increment' => TRUE
+            ],
+            'id_roles' => [
+                'name' => 'id',
+                'type' => 'bigint',
+                'constraint' => '20'
+            ]
+        ];
+
+        $this->dbforge->modify_column('ea_users', $fields);
+
+        // Users Settings
+        $fields = [
+            'id_users' => [
+                'name' => 'id_users',
+                'type' => 'bigint',
+                'constraint' => '20'
+            ]
+        ];
+
+        $this->dbforge->modify_column('ea_user_settings', $fields);
+    }
+}