PDO - Call to a member function execute() on a non-object

Question

I have a problem with PDO...
Class, in which i have an error, used for executing select (and in the future - other) queries to database, using PHP:PDO... like that:

$db = new PDOAct;
    $arr    = array("from" => "users");
    $row    = array("id");
    $val    = array(0);
    $type   = array("INT");
    $db->select($arr, $row, $val, $type);

When i execute this,

<? if (!defined("sKEY")) { exit("Houston, We've Got a Problem"); }
class PDOAct
{
    public $db;
    function __construct()
    {
        try {
            $this->db = new PDO(DBdriver.':host='.DBhost.';dbname='.DBbase, DBuser, DBpass);
            $this->db->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION );
        } catch(PDOException $e) {
            $this->err($e->getMessage());
        }
    }
    function select($arr, $row, $val, $type)
    {
        try {
            for ($i=0; $i<count($row); $i++)
            {
                if (isset($row[$i]) && isset($val[$i]) && isset($type[$i]))
                {
                    if ($arr[select] != "" && $arr[select] != "*")
                    {
                        if ($i < 1)
                        {
                            $do = $this->db->prepare("SELECT `".$arr[select]."` FROM `".$arr[from]."` WHERE `".$row[$i]."` = ':".$row[$i]."'");
                        } else {
                            $do = $do.$this->db->prepare(" AND `".$row[$i]."` = ':".$row[$i]."'");
                        }
                    } elseif ($arr[select] == "" || $arr[select] == "*") {
                        if ($i < 1)
                        {
                            $do = $this->db->prepare("SELECT * FROM `".$arr[from]."` WHERE `".$row[$i]."` = ':".$row[$i]."'");
                        } else {
                            $do = $do.$this->db->prepare(" AND `".$row[$i]."` = ':".$row[$i]."'");
                        }
                    }
                    $do->bindValue(':'.$row[$i], $val[$i], "PDO::PARAM_".$type[$i]);
                } elseif (!isset($row[$i]) && !isset($val[$i]) && !isset($type[$i])) {
                    if ($arr[select] != "" && $arr[select] != "*" && $i == 0)
                    {
                        $do = $this->db->prepare("SELECT `".$arr[select]."` FROM `".$arr[from]."`");
                    } elseif ($arr[select] == "" || $arr[select] == "*" && $i == 0) {
                        $do = $this->db->prepare("SELECT * FROM `".$arr[from]."`");
                    }
                } else {
                    exit("Query error!");
                }
            }
            var_dump($this->db->prepare("SELECT * FROM `".$arr[from]."` WHERE `".$row[0]."` = ':".$row[0]."'"));
        } catch(PDOException $e) {
            $this->err($e->getMessage());
        }
        return $do;
    }
    function err($e)
    {
        file_put_contents('log'.DIR_SEP.'PDOerrors.txt', $e."\n", FILE_APPEND);
        exit("Houston, We've Got a Problem");
    }
}
?>

it gives me a php-error: "Call to a member function execute() on a non-object"
I was trying to use var_dump(); - it gives me smth like this:

object(PDOStatement)#4 (1) { ["queryString"]=> string(40) "SELECT * FROM `users` WHERE `id` = ':id'" }

So $this->db->prepare() is OK. What's the problem? I am suffering about this over 3 hours..
THANK YOU!

Yes. There's var_dump(), but if i place here $do->execute() it gives me an error.. — ZLOI_DED, Jun 21 '13 at 22:34
Apart from the above comment, you should change `$arr[select]` to `$arr['select']` and so on. — hjpotter92, Jun 21 '13 at 22:34
Have a problem, if I try to do like that: `$db = new PDOAct; $arr = array("from" => "users"); $row = array("id", "login"); $val = array(0, "Admin"); $type = array("INT", "STR"); $db->select($arr, $row, $val, $type);` - 500 internal server error — ZLOI_DED, Jun 21 '13 at 22:45
This is wrong, see my answer: `$do = $do.$this->db->prepare(" AND `".$row[$i]."` = ':".$row[$i]."'");` — jeroen, Jun 21 '13 at 22:52

score 1 · Accepted Answer · answered Jun 21 '13 at 22:39

1

You cannot do stuff like this:

 if ($i < 1)
 {
    $do = $this->db->prepare("SELECT * FROM `".$arr[from]."` WHERE `".$row[$i]."` = ':".$row[$i]."'");
 } else {
    $do = $do.$this->db->prepare(" AND `".$row[$i]."` = ':".$row[$i]."'");
 }

You need to generate your sql statement (dynamically) and only when you have the complete statement ready, you prepare it, you cannot concatenate and prepare partial statements.

answered Jun 21 '13 at 22:39

jeroen

91,079
21
114
132

Ok.. This why that: `$db = new PDOAct; $arr = array("from" => "users"); $row = array("id", "login"); $val = array(0, "Admin"); $type = array("INT", "STR"); $db->select($arr, $row, $val, $type);` is not working? – ZLOI_DED Jun 21 '13 at 22:42
So i need to generate sql-query and put it in variable and then prepare a variable? – ZLOI_DED Jun 21 '13 at 22:57
@ZLOI_DED Yes, you need to generate a complete query string and when that is done, you use `prepare` on that string right before you execute it. Now you are concatenating objects, apart from the fact that you cannot prepare just a `AND` condition. – jeroen Jun 21 '13 at 23:01
Ok. Thank u)) That error fixed. Now i have "Call to a member function bindValue() on a non-object") It's maybe because i do it before prepare()? Code: $bindrow = ':'.$row[$i]; $bindtype = "PDO::PARAM_".$type[$i]; $do->bindValue($bindrow, $val[$i], $bindtype); It's in for()... – ZLOI_DED Jun 21 '13 at 23:07
OK! It's done! Thank u all)) – ZLOI_DED Jun 22 '13 at 00:15

score 0 · Answer 2 · answered Jun 21 '13 at 22:45

0

You are calling execute on a non-object, make sure you use the proper order

$data = array("id" => "your_row_id");
$STH = $this->db->prepare($your_query); // In which you are using your :id named placeholder
$STH->execute($data);

answered Jun 21 '13 at 22:45

Dani-san

304
2
4

Now I have an other problem: Statement is executing normally, but when i do smth like this: `$db = new PDOAct; $arr = array("from" => "users"); $row = array("id", "login"); $val = array(0, "Admin"); $type = array("INT", "STR"); $db->select($arr, $row, $val, $type);` - I get an 500 Internal Server Error... – ZLOI_DED Jun 21 '13 at 22:48

PDO - Call to a member function execute() on a non-object

2 Answers2