quick guide & examples
PHP MYSQL
CURRENT MEMORY USAGE (BYTES) echo memory_get_usage();
PEAK MEMORY USAGE (BYTES) echo memory_get_peak_usage();
CONNECT TO DATABASE $pdo = new PDO("mysql:host=HOST; dbname=NAME;charset=utf8mb4", USER, PASSWORD);
PREPARE SQL $stmt = $pdo->prepare("SELECT * FROM `TABLE`"); $stmt->execute();
BAD - FETCH ALL AT ONCE $r = $stmt->fetchAll();
GOOD - FETCH LINE-BY-LINE while ($r = $stmt->fetch()) { print_r($r); }
BAD - READ EVERYTHING INTO A STRING $contents = file_get_contents("FILE");
GOOD - READ LINE BY LINE $fh = fopen("FILE", "r"); while ($line = fgets($fh)) { echo $line; } fclose($fh);
BAD - NEEDLESS VARIABLES $varA = 123; $varB = 234; $varC = $varA + $varB;
GOOD - NO EXTRA VARIABLES $varC = 123 + 234;
TEMPORARY VARIABLES $varA = 123; $varB = 234; $varC = $varA + $varB;
REMOVE IF NO LONGER IN USE unset($varA); unset($varB); gc_collect_cycles();