Want to create three dropdown list in php from mysql different table with join querying
<p>Want to create three dropdown list in  php from mysql different table.</p>

<p>I want to create three dropdown list like Unit, Location, Department it will depend with one another like unit -HO,Delhi,Mumbai.. location-Mumbai,Pune,Nashik... Dept. IT,Admin, Account  each location have differnet account want to populat dept only which is only for that location. In my database we have create diffenet table line unit field--unit id , unit name locaiton table  location id,location name unit id, dept table dept id dept name location id 
my query run properly but how can i create dropdown menu which is dependatble to one another please help me sort this issue.</p>

<p>Thanks...</p>
