How to insert an array into a single MySQL Prepared statement w/ PHP and PDO

Question

During an online enrollment, a customer may select a number of programs which they choose to enroll for. These programs are three digit integers and are stored in an array.<

Answer 1

What you are looking for is how to do a BULK insert, this is more SQL related than to PDO itself.

You only have to do the exact same thing than with *_query, build your bulk insert query and your param array side by side.

$placeholder = array();
$values = "?, ?, ?, ...";
$args = array();
foreach ($arrays as $array) {
  $placeholder[] = $value;
  $args[] = $array['col1'];
  $args[] = $array['col2'];
  $args[] = $array['col3'];
  ...
}    
$sql = "INSERT INTO table (col1, col2, ... ) VALUES ("
     . implode('), (', $placeholder)
     . ")"; 
$stmt = $db->prepare($sql);
$db->execute($sql, $args);

This is an ugly but working algorithm, I think.

Answer 2

2 solutions

// multiple queries
$stmt = $pdo->prepare('INSERT INTO table SET memberID=:memberID, programID=:programID, date_added=NOW()');
$data = array(155, 165, 175, 185);
foreach($data as $d) {
    $stmt->execute(array(':memberID' => $memberid, ':programID' => $d));
}

And

// one query
$data = array(155, 165, 175, 185);
$values = array();
foreach($data as $d) {
    $values[] = sprintf('(%d, %d, NOW())', $d, $memberid);
}
$sql = sprintf('INSERT INTO table (memberID, programID, date_added) VALUES %s', implode (', ', $values));
$pdo->exec($sql);

Answer 3

You could build the query programatically...:

$sql = 'INSERT INTO table (memberID, programID) VALUES ';
$insertQuery = array();
$insertData = array();
foreach ($data as $row) {
    $insertQuery[] = '(?, ?)';
    $insertData[] = $memberid;
    $insertData[] = $row;
}

if (!empty($insertQuery)) {
    $sql .= implode(', ', $insertQuery);
    $stmt = $db->prepare($sql);
    $stmt->execute($insertData);
}