7.4 Beta1: variable not found in subplan target lists

Hey again,

Received this error:

Aug  6 16:24:55 thunder postgres[7835]: [11-1] ERROR:  variable not
found in subplan target lists 

during this query:
  $dbh->do( qq/
DELETE FROM temp_obs_v
WHERE file_id IN  (SELECT file_id   FROM temp_obs_v NATURAL JOIN files   WHERE  group_id = $group_id      AND pair_id
=$pair_id) /);
 

on the 15th iteration (the previous 14 worked fine).

It is repeatable.  Something stupid again (other than the duplicate
indexes)?

tassiv=# explain DELETE FROM temp_obs_i  
tassiv-# WHERE file_id IN 
tassiv-#    (SELECT file_id 
tassiv(#     FROM temp_obs_i NATURAL JOIN files
tassiv(#     WHERE  group_id = 3 
tassiv(#        AND pair_id  = 25) 
tassiv-# ;
ERROR:  variable not found in subplan target lists

tassiv=# \d temp_obs_i                    Table "public.temp_obs_i"Column  |  Type   |                   Modifiers
             
 
---------+---------+------------------------------------------------x       | real    | not nully       | real    | not
nullimag   | real    | not nullsmag    | real    | not nullloc     | spoint  | not nullobs_id  | integer | not null
defaultnextval('"obs_id_seq"'::text)file_id | integer | not nulluse     | boolean | default falsesolve   | boolean |
defaultfalsestar_id | integer | mag     | real    | 
 
Indexes:   "temp_obs_i_file_id_index" btree (file_id)   "temp_obs_i_index" gist (loc)   "temp_obs_i_loc_index" gist
(loc)  "temp_obs_i_obs_id_index" btree (obs_id)
 
Foreign-key constraints:   "temp_obs_i_files_constraint" FOREIGN KEY (file_id) REFERENCES
files(file_id) ON DELETE CASCADE Inherits: obs_root

tassiv=# \d files                                   Table "public.files" Column  |           Type           |
           Modifiers                    
 
----------+--------------------------+---------------------------------
---------------------- file_id  | integer                  | not null
default nextval('"files_file_id_seq"'::text) group_id | integer                |  pair_id  | integer                  |
date    | timestamp with time zone | not nullname     | character varying        | not nullra_min   | real
      | default 0ra_max   | real                     | default 0dec_min  | real                     | default 0dec_max
|real                     | default 0
 
Indexes:   "files_pkey" primary key, btree (file_id)   "files_name_key" unique, btree (name)   "files_id_index" btree
(file_id,group_id, pair_id)   "files_range_index" btree (ra_min, ra_max, dec_min, dec_max)
 
Foreign-key constraints:   "$1" FOREIGN KEY (group_id) REFERENCES groups(group_id) ON DELETE
CASCADE    "$2" FOREIGN KEY (pair_id) REFERENCES pairs(pair_id) ON
DELETE CASCADE



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