PDO - lastInsertId() for insert query with multiple rows

It's not possible. If you need generated ids for both rows - you need to perform 2 separated INSERT

Important If you insert multiple rows using a single INSERT statement, LAST_INSERT_ID() returns the value generated for the first inserted row only. The reason for this is to make it possible to reproduce easily the same INSERT statement against some other server.

http://dev.mysql.com/doc/refman/5.5/en/information-functions.html#function_last-insert-id

Please, please avoid the type of solutions given by Bruce. The auto increment value can be set to be different than 1. For instance in case of master to master replication. A little while back a host where one of our applications runs on changed their db setup. I happened to notice -purely by coincidence- that all of a sudden the id's incremented with two instead of one. Would we have had any code like this it could have caused us serious problems.

you can add 1 to last insert id to achieve the real last record id.and if you insert more than 2 record just add rowCount - 1 to last_insert_id.

With innodb_autoinc_lock_mode set to 0 (“traditional”) or 1 (“consecutive”), the auto-increment values generated by any given statement will be consecutive, without gaps, because the table-level AUTO-INC lock is held until the end of the statement, and only one such statement can execute at a time.

and

The ID that was generated is maintained in the server on a per-connection basis. This means that the value returned by the function to a given client is the first AUTO_INCREMENT value generated for most recent statement affecting an AUTO_INCREMENT column by that client. This value cannot be affected by other clients, even if they generate AUTO_INCREMENT values of their own. This behavior ensures that each client can retrieve its own ID without concern for the activity of other clients, and without the need for locks or transactions.

for more info read this document http://dev.mysql.com/doc/refman/5.1/en/innodb-auto-increment-handling.html