PDOlastInsertId()

你可能經常發現需要為剛剛插入資料庫表的行獲取自動遞增的 ID 值。你可以使用 lastInsertId() 方法實現此目的。

// 1. Basic connection opening (for MySQL)
$host = 'localhost';
$database = 'foo';
$user = 'root'
$password = '';
$dsn = "mysql:host=$host;dbname=$database;charset=utf8";
$pdo = new PDO($dsn, $user, $password);

// 2. Inserting an entry in the hypothetical table 'foo_user'
$query = "INSERT INTO foo_user(pseudo, email) VALUES ('anonymous', 'anonymous@example.com')";
$query_success = $pdo->query($query);

// 3. Retrieving the last inserted id
$id = $pdo->lastInsertId(); // return value is an integer

在 postgresql 和 oracle 中，有 RETURNING 關鍵字，它返回當前插入/修改的行的指定列。這裡插入一個條目的示例：

// 1. Basic connection opening (for PGSQL)
$host = 'localhost';
$database = 'foo';
$user = 'root'
$password = '';
$dsn = "pgsql:host=$host;dbname=$database;charset=utf8";
$pdo = new PDO($dsn, $user, $password);

// 2. Inserting an entry in the hypothetical table 'foo_user'
$query = "INSERT INTO foo_user(pseudo, email) VALUES ('anonymous', 'anonymous@example.com') RETURNING id";
$statement = $pdo->query($query);

// 3. Retrieving the last inserted id
$id = $statement->fetchColumn();  // return the value of the id column of the new row in foo_user