added basic user model

model/user.php

+<?php
+
+class User {
+    function getAllUser(){
+        $con = mysqli_connect('localhost','root','','projekers');
+        mysqli_select_db($con, 'projekers');
+        $sql = "SELECT * FROM user";
+        $result = mysqli_query($con, $sql);
+        mysqli_close($con);
+        return $result;
+    }
+
+    function getUserByUsername($username){
+        $con = mysqli_connect('localhost','root','','projekers');
+        mysqli_select_db($con, 'projekers');
+        $sql = "SELECT * FROM user WHERE username='" . (string)$username . "'";
+        $result = mysqli_query($con, $sql);
+        mysqli_close($con);
+        return $result;
+    }
+
+}
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