MySQL Insert failing dynamically but working directly - php

Question

I've got a MySQL table with fields a1,a2,a3,b1,...,d1,d2, each field was declared as a BOOLEAN in the CREATE statement. (I also tried TINYINT(1) but had the same problem).
Then I have this PHP function which receives data from an HTML form:
public function add($a) {
$sql = "INSERT INTO property_classification
(a1,a2,a3,b1,b2,b3,b4,b5,b6,b7,b8,c1,c2,c3,d1,d2)
VALUES(?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?);";
// creating the classification_id
// e.g. "a1a2a3" => ["a1","a2","a3"]
$classifications = str_split($a['classifications'], 2);
$data = array();
// compile $data array
foreach (self::$classification_fields as $classification) {
// if user array contained any classification, set to true
if (in_array($classification, $classifications)) {
$data[$classification] = "1"; // I tried `true` too
} else {
$data[$classification] = "0"; // I tried `false` here
}
}
// set type for binding PDO params
foreach ($data as $key=>$value) settype($data[$key], 'int'); // tried 'bool'
$this->db->query($sql, $data);
$a['classification_id'] = $this->db->lastInsertId();
$this->log($a['classification_id']); // Output: "0"
...
The output should be a valid ID from 1+, but the insert failed so the lastInsertId() returned 0.
I checked what $sql compiled to, it came to this:
INSERT INTO property_classification (a1,a2,a3,b1,b2,b3,b4,b5,b6,b7,b8,c1,c2,c3,d1,d2) VALUES(?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?);
I also output $data with the code: implode(",",$data); and it gave me this output:
1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0
Which was perfect because the input was "a1a2".
The only problem now is I don't understand why the query is failing all the time, because I put the two bits together like so:
INSERT INTO property_classification (a1,a2,a3,b1,b2,b3,b4,b5,b6,b7,b8,c1,c2,c3,d1,d2) VALUES(1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0);
Then I executed that query in MySQL Query Browser and it worked.
So why is it failing through PDO?
DBO class
function query($sql, $data) {
try {
$this->query = $this->db->prepare($sql);
if (!is_null($data) && is_array($data))
$this->query->execute($data);
else
$this->query->execute();
} catch (PDOException $e) {
array_push($this->log, $e->getMessage());
}
}

Answer 1

Since you're actually passing an associative array to the PDO, you can bind to named parameters. The use of ? or positional placeholders require a standard indexed array. If you're against using named params, just replace $data[$classification] = with $data[] =
Try the below.
public function add($a) {
$sql = "INSERT INTO property_classification
(a1,a2,a3,b1,b2,b3,b4,b5,b6,b7,b8,c1,c2,c3,d1,d2)
VALUES(:a1,:a2,:a3,:b1,:b2,:b3,:b4,:b5,:b6,:b7,:b8,:c1,:c2,:c3,:d1,:d2);";
// creating the classification_id
// e.g. "a1a2a3" => ["a1","a2","a3"]
$classifications = str_split($a['classifications'], 2);
$data = array();
// compile $data array
foreach (self::$classification_fields as $classification)
$data[$classification] = in_array($classification, $classifications) ? 1 : 0;
$this->db->query($sql, $data);
$a['classification_id'] = $this->db->lastInsertId();
$this->log($a['classification_id']); // Output: "0"