php - I'm not able to display users data -

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• php: “notice: undefined variable”, “notice: undefined index”, , “notice: undefined offset” 23 answers

it says:

1. warning: missing argument 1 users_data()
2. notice: undefined variable: user_id
3. warning: mysql_fetch_array() expects parameter 1 resource, boolean given

my function:

function users_data($user_id) {         $data =array();         $user_id = (int)$user_id;      $query = mysql_query("select * `sun` `user_id` ='$user_id'");     $user_data = mysql_fetch_array($query);     return $user_data; } 

what do?

i know $user_id not defined tell me how define $user_id

i have done $user_id = $_session['use_id'];; says undefined index...

then use $sql = "select * users user_id= ???" got stuck

can tell me how solve this?

please don't tell me add user_id = 1,2,3 etc. because working on login , registration form , displaying users data.

from warning 1 , clear didnt pass $user_id function

 users_data($user_id) // $user_id??? may have called function users_data()  

try pass $user_id users_data function, because warnings 2 , 3 depends on warning 1.