Added initial readme

Author: avbdr

dbObject.md

@@ -0,0 +1,144 @@
+dbObject - model implementation on top of the MysqliDb
+Please note, that this library is not pretending to be a full stack ORM but a simple OOP wrapper for mysqlidb
+
+<hr>
+**[Initialization] (#initialization)**
+1. Include mysqlidb and dbObject classes. 
+2. If you want to use model autoloading instead of manually including them in the scripts use autoload () method.
+
+```php
+require_once ("libs/MysqliDb.php");
+require_once ("libs/dbObject.php");
+
+// db instance
+$db = new Mysqlidb ('localhost', 'user', '', 'testdb');
+// enable class autoloading
+dbObject::autoload ("models");
+
+```
+2. Create simple user class (models/user.php):
+```php
+class user extends dbObject {
+  protected $dbTable = "users";
+  protected $primaryKey = "id";
+  protected $dbFields = Array (
+    'login' => Array ('text', 'required'),
+    'password' => Array ('text'),
+    'createdAt' => Array ('datetime'),
+    'updatedAt' => Array ('datetime'),
+  );
+}
+```
+**[Insert Row]**
+1. OOP Way. Just create new object of a needed class, fill it in and call save () method. Save will return 
+record id in case of success and false in case if insert will fail.
+```php
+$user = new user;
+$user->login = 'demo';
+$user->password = 'demo';
+$id = $user->save ();
+if ($id)
+  echo "user created with id = " . $id;
+```
+2. Using arrays
+```php
+$data = Array ('login' => 'demo',
+        'password' => 'demo');
+$user = new user ($data);
+$id = $user->save ();
+if ($id == null) {
+    print_r ($user->errors);
+    echo $db->getLastError;
+} else
+    echo "user created with id = " . $id;
+```
+
+2. Multisave
+```php
+$user = new user;
+$user->login = 'demo';
+$user->pass = 'demo';
+
+$p = new product;
+$p->title = "Apples";
+$p->price = 0.5;
+$p->seller = $user;
+$p->save ();
+```
+
+After save() is call both new objects (user and product) will be saved.
+
+**[Selects]**
+Retrieving objects from the database is pretty much the same process of a get ()/getOne () execution without a need to specify table name.
+All mysqlidb functions like where(), orWhere(), orderBy(), join etc are supported.
+Please note that objects returned with join() will not save changes to a joined properties. For this you can use relationships.
+
+Select row by primary key
+```php
+$user = user::byId (1);
+echo $user->login;
+```
+
+Get all users
+```php
+$users = user::orderBy ('id')->get ();
+foreach (users as $u) {
+  echo $u->login;
+}
+```
+
+Using where with limit
+```php
+$users = user::where ("login", "demo")->get (Array (10, 20));
+foreach (users as $u) ...
+```
+
+**[Update]**
+To update model properties just set them and call save () method. As well values that needed to by changed could be passed as an array to the save () method.
+
+```php
+$user = user::byId (1);
+$user->password = 'demo2';
+$user->save ();
+```
+```php
+$data = Array ('password', 'demo2');
+$user = user::byId (1);
+$user->save ($data);
+```
+
+**[Delete]**
+Use delete() method on any loaded object. 
+```php
+$user = user::byId (1);
+$user->delete ();
+```
+
+**[Relations]**
+Currently dbObject supports only hasMany and hasOne relations only. To use them declare $relations array in the model class like:
+```php
+    protected $relations = Array (
+        'person' => Array ("hasOne", "person", 'id');
+        'products' => Array ("hasMany", "product", 'userid')
+    );
+```
+After that you can get related object via variables and do their modification/removal/display:
+```php
+    $user = user::byId (1);
+    // sql: select * from $persontable where id = $personValue
+    echo $user->person->firstName . " " . $user->person->lastName . " have the following products:\n";
+    // sql: select * from $product_table where userid = $userPrimaryKey
+    foreach ($user->products as $p) {
+            echo $p->title;
+    }
+```
+**[Error checking]**
+TBD
+**[Validation]**
+TBD
+**[Array as return values]**
+TBD
+**[2array and 2json]**
+TBD
+
+

dbObject.php

@@ -227,10 +227,10 @@ public function update ($data = null) {
      *
      * @return mixed insert id or false in case of failure
      */
-    public function save () {
+    public function save ($data = null) {
         if ($this->isNew)
             return $this->insert();
-        return $this->update();
+        return $this->update($data);
     }
 
     /**