Re: Possible bug in PostgreSQL 8.3beta4 (postgres process segfaults)

Hello

this is bug. Please send backtrace from core file.

Regards
Pavel Stehule

On 12/12/2007, Lawrence Oluyede <l.oluyede@gmail.com> wrote:
> While developing a Python program I encountered a situation that makes
> on of the PostgreSQL 8.3b4's processes crash badly with a segfault.
> Let me explain.
>
> After enabling "debug5" as log level I was able to locate and
> reproduce the exact sequence of SQL queries made against my test
> database
> and crash postgres again using only "psql". See for yourself:
>
>
> foodb=# \o out.txt
> foodb=# SELECT * FROM foobaz.instrument WHERE code = 'TEST0118';
> LOG:  duration: 3.683 ms  statement: SELECT * FROM foobaz.instrument
> WHERE code = 'TEST0118';
> foodb=# SELECT xpath('//sp:description/text()', content,
> ARRAY[ARRAY['sp', 'http://www.foobaz.com/']])
> foodb-#        FROM foobaz.instrument WHERE code = 'TEST0018';
> server closed the connection unexpectedly
>         This probably means the server terminated abnormally
>         before or while processing the request.
> The connection to the server was lost. Attempting reset: Failed.
>
> The pgsql log file contains these error logs (the pid 753 is a
> postgres child process):
>
> """""""""
> [loluyede:foodb:2007-12-11 14:38:20.992 CET]LOG:  00000: duration:
> 0.090 ms  statement: BEGIN; SET TRANSACTION ISOLATION LEVEL READ
> COMMITTED
> [loluyede:foodb:2007-12-11 14:38:20.992 CET]LOCATION:
> exec_simple_query, postgres.c:1040
> [::2007-12-11 14:38:20.993 CET]LOG:  00000: server process (PID 753)
> was terminated by signal 11: Segmentation fault
> [::2007-12-11 14:38:20.993 CET]LOCATION:  LogChildExit, postmaster.c:2510
> [::2007-12-11 14:38:20.993 CET]LOG:  00000: terminating any other
> active server processes
> [::2007-12-11 14:38:20.993 CET]LOCATION:  HandleChildCrash, postmaster.c:2355
> [::2007-12-11 14:38:20.997 CET]LOG:  00000: all server processes
> terminated; reinitializing
> [::2007-12-11 14:38:20.997 CET]LOCATION:  PostmasterStateMachine,
> postmaster.c:2663
> [::2007-12-11 14:38:21.000 CET]LOG:  00000: database system was
> interrupted; last known up at 2007-12-11 14:38:02 CET
> [::2007-12-11 14:38:21.000 CET]LOCATION:  StartupXLOG, xlog.c:4789
> [::2007-12-11 14:38:21.000 CET]DEBUG:  00000: checkpoint record is at 0/2AB634A0
> """"""""
>
> The out.txt file contains the output of the "SELECT *" statement
>
>    code   |    kind    |         last_modified         |
> created            | modified_by | created_by |
>        content
>
----------+------------+-------------------------------+------------------------------+-------------+------------+----------------------------------------------------------------------
>  TEST0118 | bazfoo | 2007-12-12 08:17:01.846919+01 | 2007-12-12
> 08:17:00.32337+01 | anonymous   | anonymous  | <xml ... >
> (1 row)
>
> The "instrument" table has the following schema:
>
> """
> CREATE TABLE foobaz.instrument
> (
> -- Inherited:   code character varying(32) NOT NULL,
> -- Inherited:   kind character varying(32) NOT NULL DEFAULT
> 'bazfoo'::character varying,
>   last_modified timestamp with time zone NOT NULL,
>   created timestamp with time zone NOT NULL DEFAULT
> ('now'::text)::timestamp(3) with time zone,
>   modified_by character varying(64),
>   created_by character varying(64) NOT NULL DEFAULT
> 'anonymous'::character varying,
>   content xml NOT NULL,
>   CONSTRAINT instrument_pkey PRIMARY KEY (code),
>   CONSTRAINT instrument_kind_check CHECK (kind::text = 'bazfoo'::text)
> )
> INHERITS (foobaz.instrument_base)
> WITH (OIDS=FALSE);
> """
>
> Its "parent" table is instrument_base and has the following schema:
>
> """
> CREATE TABLE foobaz.instrument_base
> (
>   code character varying(32) NOT NULL,
>   kind character varying(32) NOT NULL,
>   CONSTRAINT instrument_base_pkey PRIMARY KEY (code)
> )
> WITH (OIDS=FALSE);
> """
>
> PostgreSQL is again 8.3beta 4 on Ubuntu Linux 7.10.
> It's compiled with the following flags:
> ./configure --with-python --with-openssl --with-pam --with-libxml
> --with-libxslt --enable-thread-safety --enable-debug
>
> libxml is 2.6.30, libxslt is 1.1.21
>
> I think that is all.
>
> Is it a bug or am I doing something wrong?
>
> --
> Lawrence, oluyede.org - neropercaso.it
> "It is difficult to get a man to understand
> something when his salary depends on not
> understanding it" - Upton Sinclair
>
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