multiple calls to $stmt->bind_param - php

Question

I'm in a situation where I want to build a code which gets $bindParam variable in this format:
$bindParams = [$type1 => $param1, $type2 => $param2, ... ]
I wanna build some code that dynamically adds that parameters to the prepared statement.
This is the code which I built so far :
$mysql = new mysqli("localhost", "root", "", "db1");
$stmt = $mysql->prepare($sql);
foreach($bindParams as $type => $data) {
$stmt->bind_param($type, $data);
}
$stmt->execute();
$result = $stmt->get_result();
// and after perhaps twiddling with the result set, but this is not the case .....
For your instance
$sql = "INSERT INTO table1 (name, age) VALUES (?,?);"
and
$bindParams = ["s" => "hello", "i" => 15]
This does not always have this structure and it can change to for example $bindParams = ["s" => "hello", "i" => 15, "d" => 22.5] and so the $sql changes respectively.
After the first time the compiler heads to $stmt->bind_param($type, $data); firefox flushes this error:
Warning: mysqli_stmt::bind_param(): Number of variables doesn't match number of parameters in prepared statement in D:\PHP\tr.php on line 23
I know PDO support that as stated here at the end of the page. but perhaps as you might expect Im not a fan of PDO so ;)
My other option is to use the eval() workarounds available in php but thats out of what I might think of.
Is there another way to do this?

Answer 1

I had the same problem, and found an answer much simplier:
$array_of_values = array( "Brasil", "Argentina" );
$types = "ss";
$mysqli_stmt->bind_param( $types, ...$array_of_values );
This is called "argument unpacking", and is available since PHP 5.6
http://php.net/manual/pt_BR/migration56.new-features.php

Answer 2

Sadly mysqli doesn't support this. Calling the function over and over again overwrites the values, so you're only binding one param when you clearly have more.
There's a couple of ways to get around this
Switch to PDO. You can make one bind per function call with that
Bind the params as one aggregate using call_user_func_array
$sqltype = '';
$sqldata = [];
foreach($bindParams as $type => $data) {
$sqltype .= $type;
$sqldata[] = &$data; // MUST be a reference
}
array_unshift($sqldata, $sqltype); // prepend the types
call_user_func_array([$stmt, 'bind_param'], $sqldata);

Answer 3

I use something like this to do dynamic procedure calls.
Example Call:
$mapi = new MySQLIAPI($con);
$mapi->BeginProc();
$mapi->AddParameter("user", $usern, "s");
$mapi->AddParameter("email", $email, "s");
$mapi->AddParameter("passwd", $pwd, "s");
$id = $mapi->CallProc("ij_create_user");
$id = $id[0];
if(isset($id['mysql_error']) || isset($id["error"])){
return "error";
}
return $id["id"];
Example Class:
class MySQLIAPI
{
private $con = null;
private $Variables = null;
private $values = null;
private $types = null;
private $vQu = null;
private $stmt = null;
function __construct($dbc)
{
$this->con = $dbc;
$this->Variables = [];
$this->values = [];
$this->types = [];
$this->vQu = [];
}
function BeginProc()
{
$this->stmt = $this->con->stmt_init(); // initialize statement
}
function AddParameter($key, $val, $type)
{
$this->Variables[] = "#" . $key;
$this->values[] = $val;
$this->types[] = $type;
$this->vQu[] = "?";
}
//KeyPair is v = the value, t = the type s or d
function CallProc($Proc) {
$out_var = null;
$call = "";
if(sizeof($this->values) > 0)
$call = "CALL ".$Proc."(".implode(",", (array)$this->vQu).")";
else
$call = "CALL ".$Proc."()";
if($this->stmt->prepare($call));//call stored procedure with database server session variable
{
if(sizeof($this->values) > 0) {
$params = array_merge(array(implode("", $this->types)), $this->values);
call_user_func_array(array($this->stmt, 'bind_param'), $this->refValues($params));
}
$this->stmt->execute();
$result = $this->stmt->get_result();
/* Error Checking */
$mySQLiError = mysqli_stmt_error($this->stmt);
if ($mySQLiError != "") {
$this->resetStmt();
$this->stmt->close();
$this->stmt = null;
return array('mysql_error' => $mySQLiError);
}
while ($row = $result->fetch_array(MYSQLI_ASSOC))
{
$out_var[] = $row;
}
$result->free();
while($this->stmt->more_results())
{
$this->stmt->next_result();
}
$this->resetStmt();
$this->stmt->close();
$this->stmt = null;
}
return $out_var;
}
private function refValues($arr)
{
if (strnatcmp(phpversion(), '5.3') >= 0) //Reference is required for PHP 5.3+
{
$refs = array();
foreach ($arr as $key => $value)
$refs[$key] =& $arr[$key];
return $refs;
}
return $arr;
}
private function resetStmt()
{
//Reset Params
$this->Variables = array();
$this->values = array();
$this->types = array();
$this->vQu = array();
}
}