Question

Based on this question How to insert array into mysql using PDO and bindParam?

I’m trying to insert values of an array into mysql via PDO.
I’m having a hard time of it, because I keep getting the following error.
SQLSTATE[HY093]: Invalid parameter number: number of bound variables does not match number of tokens
for this line $stmt->execute();

I’m guessing the problem has something to do with this line

$stmt->bindParam(':val$count', $val,PDO::PARAM_STR); Specifically ‘val$count’, but I’m not sure exactly what is going wrong.

QUESTION: What am I doing wrong? How can I fix this?

Anyway here is the code I’m using along with the sample array.

$lastInsertValue=87;
$qid[0][0]=1;
$qid[0][1]=1;
$qid[1][0]=2;
$qid[1][1]="null";
$qid[2][0]=3;
$qid[2][1]=0;
$array_count = count($qid);

if (isset($lastInsertValue)) 
{ 
    try 
    {
            $dbh = new PDO("mysql:host=$hostname;dbname=$dbname", $username, $password);
            $stqid=array();
            $a=0;       
                for ($i=0; $i<$array_count; $i++)
                {       
                    $stqid[$a]=$lastInsertValue;
                    $a++;
                    $stqid[$a]=$qid[$i][0];
                    $a++;
                    $stqid[$a]=$qid[$i][1];
                    $a++;
                }

            $sql = "INSERT INTO qresults (instance, qid, result) VALUES ( :val0, :val1, :val2)";
            $count = 0;
            $stmt = $dbh->prepare($sql);    
                foreach ($stqid as $val)
                {
                    $stmt->bindParam(':val$count', $val,PDO::PARAM_STR);
                    $count++;           
                }
            $stmt->execute();
            $dbh = null;
    }
    catch(PDOException $e)
    {
        echo $e->getMessage();
    }
}   

Answer 1

Yikes, so many issues.

1. Your array building is so verbose. Try this

   $stqid = array();
   foreach ($qid as $qidArr) {
       $stqid[] = $lastInsertValue; // no idea why you repeat this
       $stqid[] = $qidArr[0];
       $stqid[] = $qidArr[1];
   }
   

2. Use positional placeholders if you’re simply relying on number of arguments

   $sql = 'INSERT INTO ... VALUES (?, ?, ?)';
   

3. bindParam uses references which you are overwriting with each loop iteration. You would want to use bindValue() instead

4. Your query only has 3 placeholders but your $stqid array has 9 items. This is the source of your error.