How do I get the last inserted ID of a MySQL table in PHP?

Solution 1:

If you're using PDO, use PDO::lastInsertId.

If you're using Mysqli, use mysqli::$insert_id.

If you're still using Mysql:

Please, don't use mysql_* functions in new code. They are no longer maintained and are officially deprecated. See the red box? Learn about prepared statements instead, and use PDO or MySQLi - this article will help you decide which. If you choose PDO, here is a good tutorial.

_{But if you have to, use mysql_insert_id.}

Solution 2:

there is a function to know what was the last id inserted in the current connection

mysql_query('INSERT INTO FOO(a) VALUES(\'b\')');
$id = mysql_insert_id();

plus using max is a bad idea because it could lead to problems if your code is used at same time in two different sessions.

That function is called mysql_insert_id

Solution 3:

With PDO:

$pdo->lastInsertId();

With Mysqli:

$mysqli->insert_id;

Please, don't use mysql_* functions in new code. They are no longer maintained and are officially deprecated. See the red box? Learn about prepared statements instead, and use PDO or MySQLi - this article will help you decide which. If you choose PDO, here is a good tutorial.

Solution 4:

It's ok. Also you can use LAST_INSERT_ID()

Solution 5:

What you wrote would get you the greatest id assuming they were unique and auto-incremented that would be fine assuming you are okay with inviting concurrency issues.
Since you're using MySQL as your database, there is the specific function LAST_INSERT_ID() which only works on the current connection that did the insert.
PHP offers a specific function for that too called mysql_insert_id.