MySQL的PHP​​自動增量列

Question

我如何向這些語句添加稱為ID的自動遞增列：

$sql = "CREATE TABLE IF NOT EXISTS ".$username." (uid varchar(255), tweet varchar(255))";
$alter = "ALTER TABLE ".$username." ADD UNIQUE (uid)";

謝謝

Answer 1

$sql = "CREATE TABLE IF NOT EXISTS ".$username." (ID int not null auto_increment primary key, uid varchar(255), tweet varchar(255))";

Answer 2

我會做

"CREATE TABLE IF NOT EXISTS ".$username." (id MEDIUMINT AUTO_INCREMENT PRIMARY KEY, uid varchar(255) UNIQUE, tweet varchar(255))";