postgresql - perform true on joined tables -

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in postgresql 8.4.13 have 2 tables representing card games (each 3 players) , score results of games. players identified id column , games gid:

# \d pref_games                                     table "public.pref_games"  column |            type             |                        modifiers --------+-----------------------------+----------------------------------------------------------  gid    | integer                     | not null default nextval('pref_games_gid_seq'::regclass)  rounds | integer                     | not null  stamp  | timestamp without time zone | default now() indexes:     "pref_games_pkey" primary key, btree (gid) referenced by:     table "pref_scores" constraint "pref_scores_gid_fkey" foreign key (gid) references pref_games(gid) on delete cascade  # \d pref_scores          table "public.pref_scores"  column  |         type          | modifiers ---------+-----------------------+-----------  id      | character varying(32) | not null  gid     | integer               | not null  money   | integer               | not null  last_ip | inet                  |  quit    | boolean               | indexes:     "pref_scores_pkey" primary key, btree (id, gid)     "pref_scores_gid_index" btree (gid) foreign-key constraints:     "pref_scores_gid_fkey" foreign key (gid) references pref_games(gid) on delete cascade     "pref_scores_id_fkey" foreign key (id) references pref_users(id) on delete cascade

i'm trying find out if player id='ok261593357402' has ever played player id='mr3689735717800138910' - can allow them grade each other @ web site.

i think need call perform true on inner join - correct please?

so i'm trying:

# select * pref_games g inner join pref_scores s on (s.gid=g.gid) s.id='ok261593357402';    gid   | rounds |           stamp            |       id       |   gid   | money |    last_ip     | quit ---------+--------+----------------------------+----------------+---------+-------+----------------+------  2124241 |     20 | 2013-05-01 12:26:54.052086 | ok261593357402 | 2124241 |    28 | 93.232.91.105  | f  2125575 |     17 | 2013-05-01 16:53:21.090822 | ok261593357402 | 2125575 |    32 | 93.232.91.105  | f  2125881 |     20 | 2013-05-01 17:47:26.15633  | ok261593357402 | 2125881 |   -31 | 93.232.91.105  | f  2126242 |      0 | 2013-05-01 18:41:06.769132 | ok261593357402 | 2126242 |     0 | 93.232.91.105  | f  2126244 |      0 | 2013-05-01 18:41:12.495192 | ok261593357402 | 2126244 |     0 | 93.232.91.105  | t  2126259 |      0 | 2013-05-01 18:42:39.974518 | ok261593357402 | 2126259 |     0 | 93.232.91.105  | t  2126613 |     33 | 2013-05-01 19:27:11.88462  | ok261593357402 | 2126613 |  -132 | 93.232.91.105  | f  2126813 |      0 | 2013-05-01 19:57:05.23061  | ok261593357402 | 2126813 |     0 | 93.232.91.105  | t  2127299 |     20 | 2013-05-01 20:36:42.021133 | ok261593357402 | 2127299 |   136 | 93.232.91.105  | f  2127821 |      0 | 2013-05-01 21:33:32.168757 | ok261593357402 | 2127821 |     0 | 93.232.91.105  | f  2127830 |      0 | 2013-05-01 21:34:47.694645 | ok261593357402 | 2127830 |     0 | 93.232.91.105  | t  2128012 |     21 | 2013-05-01 22:04:03.850061 | ok261593357402 | 2128012 |    55 | 93.232.91.105  | f  2129551 |     13 | 2013-05-02 10:08:37.348426 | ok261593357402 | 2129551 |   -32 | 79.250.39.175  | f  2129818 |     13 | 2013-05-02 11:21:50.998484 | ok261593357402 | 2129818 |    71 | 79.250.39.175  | f  2130467 |     11 | 2013-05-02 13:55:00.034698 | ok261593357402 | 2130467 |   -79 | 79.250.39.175  | f  2130470 |      0 | 2013-05-02 13:55:41.298932 | ok261593357402 | 2130470 |     0 | 79.250.39.175  | f  2130476 |      0 | 2013-05-02 13:56:22.359713 | ok261593357402 | 2130476 |     0 | 79.250.39.175  | f .....

but see id='ok261593357402' above, i.e. expecting see game partners too, not delivered.

i've tried:

# select * pref_games g left outer join pref_scores s on (s.gid=g.gid) s.id='ok261593357402';    gid   | rounds |           stamp            |       id       |   gid   | money |    last_ip     | quit ---------+--------+----------------------------+----------------+---------+-------+----------------+------  2124241 |     20 | 2013-05-01 12:26:54.052086 | ok261593357402 | 2124241 |    28 | 93.232.91.105  | f  2125575 |     17 | 2013-05-01 16:53:21.090822 | ok261593357402 | 2125575 |    32 | 93.232.91.105  | f  2125881 |     20 | 2013-05-01 17:47:26.15633  | ok261593357402 | 2125881 |   -31 | 93.232.91.105  | f  2126242 |      0 | 2013-05-01 18:41:06.769132 | ok261593357402 | 2126242 |     0 | 93.232.91.105  | f  2126244 |      0 | 2013-05-01 18:41:12.495192 | ok261593357402 | 2126244 |     0 | 93.232.91.105  | t  2126259 |      0 | 2013-05-01 18:42:39.974518 | ok261593357402 | 2126259 |     0 | 93.232.91.105  | t  2126613 |     33 | 2013-05-01 19:27:11.88462  | ok261593357402 | 2126613 |  -132 | 93.232.91.105  | f  2126813 |      0 | 2013-05-01 19:57:05.23061  | ok261593357402 | 2126813 |     0 | 93.232.91.105  | t ...

unfortunately same result...

should maybe make series of selects combined exists in instead?

i'm trying find out if player id='ok261593357402' has ever played player id='mr3689735717800138910'

it's shorter / faster / simpler / more elegant use if exists ... in plpgsql perform trailing if found ...:

if exists (    select 1      pref_scores p1    join   pref_scores p2 using (gid)     p1.id = 'ok261593357402'    ,    p2.id = 'mr3689735717800138910'    )    -- stuff end if;

you don't need table pref_games @ answer question.


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