<?php
// to run this script this user needs to be able to access both databases
$userName = "root";
$password = "";
$hostName = "localhost";
$database = "db_name";
$wpPrefix = "wp_"; // wordpress prefix

// Connect to the Database
$connection = new mysqli($hostName, $userName, $password, $database);

if ($mysqli->connect_errno) {
    print(sprintf("error connecting to host %s, by user %s", $hostName, $userName));
    exit();
}

$query = '
SELECT
      ju.id AS user_id,
      REPLACE(TRIM(LOWER(a.username)), \' \', \'_\') AS user_nicename,
      ju.email AS user_email,
      ju.params AS user_params,
      CASE ju.usertype
       	WHEN \'Super Administrator\' THEN 10
       	WHEN \'Administrator\' THEN 9
       	WHEN \'Manager\' THEN 8
       	WHEN \'Public Backend\' THEN 7
       	WHEN \'Publisher\' THEN 6
       	WHEN \'Editor\' THEN 5
       	WHEN \'Author\' THEN 4
       	WHEN \'Publisher\' THEN 3
       	WHEN \'Editor\' THEN 2
       	WHEN \'Author\' THEN 1
       	ELSE 0
      END AS user_status,
      CASE a.block
       	WHEN 1 THEN 2
       	ELSE 0
      END AS user_block,
      ju.name AS display_name
 FROM
      db_name.jos_users ju
 ORDER BY
      ju.id
      ';

$results = $mysqli->query($query);
while ($row = $mysqli->fetch_assoc($results)) {
    $this_id = $row['user_id'];
    $this_name = $row['user_nicename'];
    $this_email = $row['user_email'];
    $this_status = $row['user_status'];
    $this_block = $row['user_block'];
    $this_params = $row['user_params'];
    $this_dispname = $row['display_name'];

    $wp_capabilities = ($this_status == 10) ? 'a:1:{s:13:\"administrator\";s:1:\"1\";}' : 'a:1:{s:10:\"subscriber\";s:1:\"1\";}';

    $insert_query = sprintf("
 INSERT INTO wp_usermeta
 ( user_id, meta_key, meta_value )
 VALUES
 ( $this_id, 'first_name', '%s' ),
 ( $this_id, 'last_name', '%s' ),
 ( $this_id, 'nickname', '%s' ),
 ( $this_id, 'description', ' ' ),
 ( $this_id, 'rich_editing', true ),
 ( $this_id, 'comment_shortcuts', false ),
 ( $this_id, 'admin_color', 'fresh' ),
 ( $this_id, 'use_ssl', 0 ),
 ( $this_id, 'show_admin_bar_front', true ),
 ( $this_id, 'show_admin_bar_admin', false ),
 ( $this_id, 'aim', ' ' ),
 ( $this_id, 'yim', ' ' ),
 ( $this_id, 'jabber', ' ' ),
 ( $this_id, '%scapabilities', '%s' ),
 ( $this_id, '%suser_level', '%s' );
      	",
        $this_name,
        $this_name,
        $this_name,
        $wpPrefix,
        $wp_capabilities,
        $wpPrefix,
        $this_status
    );

    $insert_result = $mysqli->query($insert_query);
    print_r($insert_result);
}