BUG #7556: "select not in sub query" plan very poor vs "not exists"

The following bug has been logged on the website:

Bug reference:      7556
Logged by:          lt
Email address:      l1t@tom.com
PostgreSQL version: 9.2.0
Operating system:   windows xp
Description:        =


test=3D# create table sli_test (id int primary key,info varchar(20));
test=3D# insert into sli_test select
generate_series(1,1000000),'digoal'||generate_series(1,1000000);
test=3D# analyze verbose sli_test;
test=3D# create table sli_test2 (id int not null,info varchar(20));
test=3D#  insert into sli_test2 select
generate_series(1,1000000),'dbase'||generate_series(1,1000000);
test=3D# analyze verbose sli_test2;
test=3D# explain select max(a.info)from sli_test a where a.id not in(select
b.id from sli_test2 b where b.id<50000);
                                      QUERY PLAN
---------------------------------------------------------------------------=
------------
 Aggregate  (cost=3D9241443774.00..9241443774.01 rows=3D1 width=3D12)