test_pg_drop_delete.sql

create or replace function propagate_table_with_data()
RETURNS integer AS $$
DECLARE
  count integer;
  sql text;
begin
  count = 1;
  LOOP 
    sql = 'insert into computer(computer_id, computer_ram, cpu_id, video_id, bigstring) values';
    sql = sql || '('|| count ||', ' || random()*1024 || ', 1, 1, repeat(''P'', 1000))';
    EXECUTE sql;
    count = count + 1;
    EXIT WHEN count > 100000000; -- create 100M rows, 
  END LOOP;  
  return count;	
END;
$$ LANGUAGE plpgsql;	

drop table computer;

create table computer (
computer_id serial primary key, -- 4B
computer_ram integer, -- 4B
bigstring TEXT,
cpu_id integer, --4B
video_id integer -- 4B
); -- 40 B totalper row

-- vacuum computer; -- unneeded after a truncate, apparently: http://www.postgresql.org/docs/8.4/static/sql-truncate.html
select * from propagate_table_with_data();

SELECT reltuples FROM pg_class WHERE relname = 'computer';


-- perform experiments here:

--  XXXs to create...

truncate table computer; -- 100M 5516ms, + 76ms to drop
drop table computer; --  5680ms + 381ms to recreate
-- delete from computer; -- known to be super slow