On the iSeries and maybe other db2 platforms, this function is not defined--PHP Fatal error:  Call to undefined function  db2_last_insert_id().

The alternative is to use IDENTITY_VAL_LOCAL().

The above example becomes:

<?php

$database = "SAMPLE";
$user = "db2inst1";
$password = "ibmdb2";

$conn = db2_connect($database, $user, $password);
if($conn) {
    $createTable = "CREATE TABLE lastInsertID 
      (id integer GENERATED BY DEFAULT AS IDENTITY, name varchar(20))";
    $insertTable = "INSERT INTO lastInsertID (name) VALUES ('Temp Name')";
    $getIdentity = "SELECT IDENTITY_VAL_LOCAL() AS LASTID FROM SYSIBM.SYSDUMMY1";

    $stmt = @db2_exec($conn, $createTable);

    /* Checking for single row inserted. */
    $stmt = db2_exec($conn, $insertTable);

    $stmt = db2_exec($conn, $getIdentity);
    $row = db2_fetch_assoc($stmt);
    $ret = $row['LASTID'];

    if($ret) {
        echo "Last Insert ID is : " . $ret . "\n";
    } else {
        echo "No Last insert ID.\n";
    }
    
    db2_close($conn);
}
else {
    echo "Connection failed.";
}
?>