CREATE FUNCTION apply_billing_stop_function() RETURNS TRIGGER AS $apply_billing_stop_function$
  DECLARE
    result RECORD;
  BEGIN
    // Problem SELECT which I believe is source of long execution time
    SELECT
      route, class, destid, description, init, inc, rate, cost,
      CEIL(NEW.duration::float / routes.inc) * routes.inc AS billtime,
      ((CEIL(NEW.duration::float / routes.inc) * routes.inc)::float / 60) * routes.rate AS total
    INTO result FROM routes
    WHERE
      routes.class = (SELECT class FROM clients WHERE prefix = NEW.prefix) AND
      SUBSTR(NEW.callee, (CASE WHEN (SELECT strip1 FROM providers WHERE destid = routes.destid) AND SUBSTR(NEW.callee, 1, 1) = '1' THEN 2 ELSE 1 END)) LIKE routes.route || '%' AND
      active
    ORDER BY routes.route DESC, routes.rate ASC LIMIT 1;

    IF result.billtime < result.init AND result.billtime > 0 THEN
      result.billtime := result.init;
    END IF;

    NEW.client := (SELECT name FROM clients WHERE prefix = NEW.prefix);

    NEW.route := result.route;
    NEW.class := result.class;
    NEW.description := result.description;
    NEW.init := result.init;
    NEW.inc := result.inc;
    NEW.billtime := result.billtime;
    NEW.rate := result.rate;
    NEW.cost := result.cost;
    NEW.total := result.total;

    DELETE FROM cdrs_current WHERE channel = NEW.channel;

    RETURN NEW;
  END;
$apply_billing_stop_function$ LANGUAGE 'plpgsql';

CREATE TRIGGER apply_billing_stop BEFORE INSERT ON cdrs FOR EACH ROW EXECUTE PROCEDURE apply_billing_stop_function();


               QUERY PLAN for SELECT in TRIGGER executed from CLI (No PREPARE, not sure if necessary)
--------------------------------------------------------------------------------------------------------------------
 Limit  (cost=6380.77..6380.77 rows=1 width=57) (actual time=83.238..83.239 rows=1 loops=1)
   InitPlan
     ->  Seq Scan on clients  (cost=0.00..15.75 rows=2 width=4) (actual time=0.009..0.013 rows=1 loops=1)
           Filter: ((prefix)::text = '369369'::text)
   ->  Sort  (cost=6365.02..6366.25 rows=495 width=57) (actual time=83.234..83.234 rows=1 loops=1)
         Sort Key: route, rate
         ->  Seq Scan on routes  (cost=0.00..6342.86 rows=495 width=57) (actual time=17.164..83.216 rows=1 loops=1)
               Filter: (("class" = $0) AND ('4254556000'::text ~~ ((route)::text || '%'::text)) AND active)



                  Table "public.cdrs"
   Column    |            Type             | Modifiers
-------------+-----------------------------+-----------
 direction   | character varying           |
 protocol    | character varying           |
 channel     | integer                     |
 prefix      | character varying           |
 client      | character varying           |
 duration    | double precision            |
 ringtime    | double precision            |
 code        | integer                     |
 endedby     | character varying           |
 caller      | character varying           |
 callee      | character varying           |
 host        | character varying           |
 gateway     | character varying           |
 route       | character varying           |
 class       | integer                     |
 description | character varying           |
 init        | integer                     |
 inc         | integer                     |
 billtime    | integer                     |
 rate        | double precision            |
 cost        | double precision            |
 total       | double precision            |
 starttime   | timestamp without time zone |
 stoptime    | timestamp without time zone |
Triggers:
    apply_billing_stop BEFORE INSERT ON cdrs FOR EACH ROW EXECUTE PROCEDURE apply_billing_stop_function()


           Table "public.clients"
   Column    |       Type        | Modifiers
-------------+-------------------+-----------
 name        | character varying |
 prefix      | character varying |
 class       | integer           |
 rtp_forward | character varying |
 type        | character varying |
 balance     | double precision  |
 active      | boolean           |


         Table "public.providers"
  Column  |       Type        | Modifiers
----------+-------------------+-----------
 destid   | integer           |
 name     | character varying |
 alias    | character varying |
 prefix   | character varying |
 protocol | character varying |
 host     | character varying |
 port     | integer           |
 strip1   | boolean           |
 active   | boolean           |


            Table "public.routes"
   Column    |       Type        | Modifiers
-------------+-------------------+-----------
 route       | character varying | not null
 lata        | character varying |
 ocn         | character varying |
 rate        | double precision  |
 cost        | double precision  |
 init        | integer           |
 inc         | integer           |
 city        | character varying |
 state       | character varying |
 country     | character varying |
 description | character varying |
 class       | integer           |
 destid      | integer           |
 active      | boolean           |
Indexes:
    "routes_pkey" PRIMARY KEY, btree (route)


Any help would be hugely appreciated.  :)