Re: Linking 2 or more databases (new incident). - Mailing list pgsql-general

From Leif Jensen
Subject Re: Linking 2 or more databases (new incident).
Date
Msg-id Pine.LNX.4.21.0210251104130.22565-100000@samba.crysberg.dk
Whole thread Raw
In response to Re: Linking 2 or more databases.  (Leif Jensen <leif@crysberg.dk>)
List pgsql-general
    Hi All,

   I'm still trying to figure out how to connect to several tables in
remote database(s) using the contrib/dblink lib. I have succeeded in
crashing the postmaster several times. My last attempt was just to show
the pointers returned from the dblink call.

   When connecting to only one 'foreign' table I got the bunch of values
back that I would expect, i.e it works fine, but when trying two tables
(from the same remote database) it runs for a long time using 100% cpu
with a lot of disk access and then finally crashes.

   This is what I did (it also includes a 'tail -f' on the postgres log
file):

leif@casper$ psql -c "select u1.dblink_p, u2.dbl_p from
(select dblink('host=limbo dbname=mydb', 'select employee, firstname
from employee') as dblink_p) u1, (select dblink('host=limbo
dbname=mydb', 'select ordre, rekvisitionsnr from ut_order where
rekvisitionsnr is not null') as dbl_p) u2;" actoverview
DEBUG:  server process (pid 20923) was terminated by signal 9
DEBUG:  terminating any other active server processes
NOTICE:  Message from PostgreSQL backend:
    The Postmaster has informed me that some other backend
    died abnormally and possibly corrupted shared memory.
    I have rolled back the current transaction and am
    going to terminate your database system connection and exit.
    Please reconnect to the database system and repeat your query.
DEBUG:  all server processes terminated; reinitializing shared memory and
semaphores
DEBUG:  database system was interrupted at 2002-10-24 16:53:14 CEST
DEBUG:  checkpoint record is at 0/1943BC0
DEBUG:  redo record is at 0/1943BC0; undo record is at 0/0; shutdown FALSE
DEBUG:  next transaction id: 2182; next oid: 130338
DEBUG:  database system was not properly shut down; automatic recovery in
progress
DEBUG:  ReadRecord: record with zero length at 0/1943C00
DEBUG:  redo is not required
DEBUG:  database system is ready
message type 0x44 arrived from server while idle
server closed the connection unexpectedly
    This probably means the server terminated abnormally
    before or while processing the request.
connection to server was lost



   I'm running on

 PostgreSQL v.7.2.3,
 Linux 2.4.19 (Slackware 8.1).

   and the remote server that I'm using is

 PostgreSQL v.7.2.1,
 Linux 2.4.18 (Slackware 8.0)

   but from the log on the remote, it seems that it never did connect to
it.


  Please help,

 Leif



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