php - insert data by GET -

i want insert data in sql can not insert data

<?php  include("config.php");  $f=$_get["first_name"]; $l=$_get["last_name"]; $e=$_get["email"]; $m=$_get["mobile"]; $b=$_get["birthday"]; $g=$_get["gender"];    $insert="insert user ( `first_name`, `last_name`, `email`, `mobile`, `birthday`, `gender`) values ('$f', '$l', '$e', '$m', '$b', '$g')"; mysqli_query($insert);    ?> 

i try insert data link :

http://localhost:8888/restfull/insert.php?f=hayoo

it's been long time since have used mysqli code below should run though. others have mentioned never bind unsanitized data (even if think trust data it's safe use prepared statements still).

<?php //create db connection  $conn = new mysqli('server', 'user', 'password', 'databasename'); //create insert statement. never concat un-sanitized data in statements  $insert="insert user ( `first_name`, `last_name`, `email`, `mobile`, `birthday`, `gender`) values (?, ?, ?, ?, ?, ?)";   $stmt = $conn->prepare($sql);  //values corespond ? except first param represents format of expected data. "s" stands string $stmt->bind_param(     'ssssss',       $_get["first_name"],       $_get["last_name"],      $_get["email"],      $_get["mobile"],      $_get["birthday"],      $_get["gender"] ); $stmt->execute(); 

your url this: http://localhost:8888/restfull/insert.php?first_name=john&last_name=doe&email=test@test.com&mobile=0&birthday=may&gender=male

make sure if putting url above in type of form correctly url encode values (i notice many of values collecting require slashes etc).