SQL function very slow compared to query without function wrapper

Question

I have this PostgreSQL 9.4 query that runs very fast (~12ms):

SELECT 
  auth_web_events.id, 
  auth_web_events.time_stamp, 
  auth_web_events.description, 
          


        

Answer 1

You will get better performance by making this query dynamic and using plpgsql.

CREATE OR REPLACE FUNCTION get_web_events_by_userid(uid int) RETURNS TABLE(
    id int,
    time_stamp timestamp with time zone,
    description text,
    origin text,
    userlogin text,
    customer text,
    client_ip inet
     ) AS $$
BEGIN

RETURN QUERY EXECUTE
'SELECT 
  auth_web_events.id, 
  auth_web_events.time_stamp, 
  auth_web_events.description, 
  auth_web_events.origin,  
  auth_user.email AS user, 
  customers.name AS customer,
  auth_web_events.client_ip
FROM 
  public.auth_web_events, 
  public.auth_user, 
  public.customers
WHERE 
  auth_web_events.user_id_fk = auth_user.id AND
  auth_user.customer_id_fk = customers.id AND
  auth_web_events.user_id_fk = ' || uid ||
'ORDER BY
  auth_web_events.id DESC;'

END;
$$ LANGUAGE plpgsql;