php - how to create the sql_query -

i have created filters in php.3 of them aimming 1 table. 4th aimming table. first table :

id_of_orders : id_order(int) time(now) username(varchar) price(decimal) 

the second 1 :

order :  order_id(int)  product(varchar) price (decimal) 

order.order_id refered id_of_orders.id_order

table id_of_orders mapper orders table (id_of_orders.id_order has unique numbers). table orders contains many orders of them have same order_id

i want return id_of_orders.id_order contain order.product=='proion'

the query use this:

$query = "select * id_of_orders 1=1"; if(!empty($_session['employees']))   $query .= " , id_of_orders.username='$_session[employees]'"; if(!empty($_session['timis']))   $query .= " , id_of_orders.price='$_session[timis]'"; if(!empty($_session['dates']))   $query .= " , date(time)='$_session[dates]'"; //if(!empty($_session['proions']))  // $query .= " , (orders.product='$_session[proions]' && id_of_orders.id_order==orders.order_id)";  $result = mysql_query($query); 

you can try query like

select o.*    id_of_orders join (   select order_id     orders    product = 'proion'    group order_id ) q on i.id_order = q.order_id  o.username = ?    , o.price = ?    , date(time) = ? 

or

select i.id_order, i.time, i.username, i.price    id_of_orders join orders o     on i.id_order = o.order_id  1 = 1    , o.product = 'proion'    , o.username = ?    , o.price = ?    , date(time) = ?  group i.id_order, i.time, i.username, i.price