(PHP 5 >= 5.1.0, PECL pdo >= 0.1.0)
PDO::lastInsertId — Returns the ID of the last inserted row or sequence value
$name = NULL
  ] )
   Returns the ID of the last inserted row, or the last value from a
   sequence object, depending on the underlying driver. For example,
   PDO_PGSQL requires you to specify the name of
   a sequence object for the name parameter.
  
Note:
This method may not return a meaningful or consistent result across different PDO drivers, because the underlying database may not even support the notion of auto-increment fields or sequences.
nameName of the sequence object from which the ID should be returned.
   If a sequence name was not specified for the name
   parameter, PDO::lastInsertId() returns a
   string representing the row ID of the last row that was inserted into
   the database.
  
   If a sequence name was specified for the name
   parameter, PDO::lastInsertId() returns a
   string representing the last value retrieved from the specified sequence
   object.
  
If the PDO driver does not support this capability, PDO::lastInsertId() triggers an IM001 SQLSTATE.