GREEN IT Developer 🌍💚: Avoid running SQL queries inside...

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GREEN IT Developer 🌍💚: Avoid running SQL queries inside a loop

SQL queries inside a loop ➰ seriously hinder performance 💪, especially if the SQL server(s) are not on the local machine. That is because these servers are designed to handle several selections, insertions, or modifications in one single query or transaction.

Wrongly used, these queries unnecessarily consume CPU power ⚡, RAM 💾 and bandwidth 🌐.

Instead of:

foreach ($userList as $user) {
    $query = 'INSERT INTO users (first_name,last_ name)
     VALUES("' . $user['first_name'] . '", "' . $user['last_name'] . '")'; 
    mysql_query($query);
}

write:

$userData = array();
foreach ($userList as $user) {
    $userData[] = '("' . $user['first_name'] . '",  "'. $user['last_name'] . '")';
}
$query = 'INSERT INTO users (first_name,last_name)
 VALUES' . implode(',', $userData); mysql_query($query);