SQLSTATE XX000 Internal Error 7

G'day all,

I'm going to go slowly on this, but I am intermittently (as in sometimes the query works fine, sometimes it stops after
5minutes and I get the message) receiving the error message below on a long running query that is populating a newly
createdtable with a PostGIS Geometry column.  

The Error Message is :

SQLSTATE[XX000]: Internal error: 7 ERROR:  could not open file "base/102979/430122_fsm": Invalid argument

I don't seem to be able to leverage any search engine to explain what this message means - To many quotes, colons and
bracketsfor google. I'm not even sure why a file is being opened, but I assume that the file is part of the data
storage- which maybe I need to know about, but I haven't so far! 

I have also fiddled a bit with the postgresql.conf settings to increase work men etc. The details of the table and
queryare below. 

So my question is really - what does this error message mean, and where do I start looking for what could be causing
it.Should I try a debug trace, or just looking in the logs (I've attached the log entries at the bottom, but maybe I
shouldup the logging level)? 

I haven't yet posted this to the postgis list, as it looked as though this message is a postgresql message, not a
postgisone.  

cheers

Ben



I'm running on :

PostgreSQL 9.1.3 on x86_64-apple-darwin11.3.0, compiled by i686-apple-darwin11-llvm-gcc-4.2 (GCC) 4.2.1 (Based on Apple
Inc.build 5658) (LLVM build 2336.9.00), 64-bit 

and PostGIS :

POSTGIS="1.5.3" GEOS="3.3.2-CAPI-1.7.2" PROJ="Rel. 4.7.1, 23 September 2009" LIBXML="2.7.3" USE_STATS






The table definition at the time that the error is occurring is:

                                        Table "system.ctybnda2009"
  Column   |            Type             |                           Modifiers
-----------+-----------------------------+----------------------------------------------------------------
 recordid  | integer                     | not null default nextval('ctybnda2009_recordid_seq'::regclass)
 ccode     | character varying(3)        |
 year      | integer                     | not null default 2005
 fips      | character varying(2)        |
 l_1_name  | character varying           |
 l_2_name  | character varying           |
 l_3_name  | character varying           |
 area      | numeric                     |
 modfiedon | timestamp without time zone | not null default now()
 the_geom  | geometry                    |
Indexes:
    "ctybnda2009_recordid_key" UNIQUE CONSTRAINT, btree (recordid)
Check constraints:
    "enforce_dims_the_geom" CHECK (st_ndims(the_geom) = 2)
    "enforce_geotype_the_geom" CHECK (geometrytype(the_geom) = 'MULTIPOLYGON'::text OR the_geom IS NULL)
    "enforce_srid_the_geom" CHECK (st_srid(the_geom) = 4326)


The query that causes the problem is :

INSERT INTO system.ctybnda2009 (ccode, the_geom)
    SELECT m.country, st_multi(st_union(m.geom))
    FROM maptable m
    LEFT OUTER JOIN countries c
        ON m.country = c.ccode
    WHERE geom IS NOT NULL
        AND m.valstart <= 2009
        AND (m.valend IS NULL OR m.valend >= 2009)
GROUP BY 1
ORDER BY 1;

postgresql.log

2012-05-03 05:18:23 WSTERROR:  could not open file "base/102979/430122_fsm": Invalid argument
2012-05-03 05:18:23 WSTSTATEMENT:  INSERT INTO system.ctybnda2011 (ccode, the_geom) SELECT m.country,
st_multi(st_union(m.geom))FROM maptable m LEFT OUTER JOIN countries c ON m.country = c.ccode WHERE geom IS NOT NULL AND
m.valstart<= $1 AND (m.valend IS NULL OR m.valend >= $2) GROUP BY 1 ORDER BY 1;