tanga_social_development=# explain analyze select * from preferences where paranoid_about_privacy = false limit 1;
                                                    QUERY PLAN
------------------------------------------------------------------------------------------------------------------
 Limit  (cost=0.00..0.02 rows=1 width=26) (actual time=0.015..0.016 rows=1 loops=1)
   ->  Seq Scan on preferences  (cost=0.00..450.35 rows=27652 width=26) (actual time=0.013..0.013 rows=1 loops=1)
         Filter: (NOT paranoid_about_privacy)
 Total runtime: 0.040 ms
(4 rows)

tanga_social_development=# explain analyze select * from preferences where paranoid_about_privacy = true limit 1;
                                                                             QUERY PLAN
---------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Limit  (cost=0.00..0.11 rows=1 width=26) (actual time=22.101..22.102 rows=1 loops=1)
   ->  Index Scan using index_preferences_on_paranoid_about_privacy on preferences  (cost=0.00..41.86 rows=383 width=26) (actual time=22.099..22.099 rows=1 loops=1)
         Index Cond: (paranoid_about_privacy = true)
         Filter: paranoid_about_privacy
 Total runtime: 22.181 ms
(5 rows)

tanga_social_development=# \d preferences
                                           Table "public.preferences"
         Column         |            Type             |                        Modifiers
------------------------+-----------------------------+----------------------------------------------------------
 id                     | integer                     | not null default nextval('preferences_id_seq'::regclass)
 user_id                | integer                     | not null
 paranoid_about_privacy | boolean                     | default false
 created_at             | timestamp without time zone |
 updated_at             | timestamp without time zone |
 receive_email          | boolean                     | default true
Indexes:
    "preferences_pkey" PRIMARY KEY, btree (id)
    "index_preferences_on_paranoid_about_privacy" btree (paranoid_about_privacy)
    "index_preferences_on_user_id" btree (user_id)
    "test_index" btree (user_id, paranoid_about_privacy)