How to use autocomplete searching two tables

I have two tables, 'states' and 'cities' and I would like the auto-complete to search any result in the two tables from the fields state and city. I haven't been able to do it yet but I have been able to search one table but cant seem to figure out how to search both.

Tables:

States
======
id
state

Cities
======
id
city

This is how I am looping through the result...

while (开发者_C百科$row = mysql_fetch_array($fetch, MYSQL_ASSOC)) {

    $row_array['id'] = $row['stateid'];
    $row_array['value'] = $row['state'];

    array_push($return_arr,$row_array);
}

When you connect to MySQL, instead of using a query on a single table, use this

select 'state' as type, id, state
from states
union all
select 'city', id, city
from cities

The resultant column named "State" contains states as well as city names. You will probably want to use the "type" column as well to identify whether the chosen name (from the array) is a state or city.

It may be easier to do a wrapper around it, so that you can filter on the combined result:

SELECT type, id, state
FROM
(
    select 'state' as type, id, state
    from states
    union all
    select 'city', id, city
    from cities
) X
WHERE ...  # you can put a where clause here