Dump produces file with new line characters

"Mark Spruill" <mark.spruill@mightyautoparts.com> writes:

We are using Postgres 7.3 on Red Hat 9. We are doing dumps with a script that does:
pg_dump databasename > outfile 2>> logfile
The resulting dump files occasionally have a \N at the end of a line of data following the copy command. This causes a problem when I try to load them back in bacause psql thinks the \N (a new line character?) is a psql command. So, how do I avoid the \N in the dump and/or ignore it in the reload?

This is a new one on me. Can you show a specific example?

Also, 7.3.what exactly?

regards, tom lane

Tom,

Thanks for the reply. psql --version reports 7.3.2.

Following is an excerpt from the dump file.

COPY compmstr (alienvendorcode, alienlinecode, alienpartnumber, jobber, list, da
te, replacedbypart, specialmarkets, discount) FROM stdin;
001 66 16-4002 32.50 65.65 2003-05-26 00:00:00
\N 0.00 0.00
001 66 16-4003 32.50 65.65 2003-05-26 00:00:00
\N 0.00 0.00
001 66 16-4006 32.50 65.65 2003-05-26 00:00:00
\N 0.00 0.00
001 66 16-4013 32.50 65.65 2003-05-26 00:00:00
\N 0.00 0.00

See what I mean? I am wondering if there is actually a new line character in the database or if the \N is representing a NULL value?

FYI, this statement in the live database:

select * from compmstr where alienvendorcode = '001' and alienpartnumber = '16-4002';

Provided this results exported from pgadmin with quotes:

"001","66","16-4002 ","32.50","65.65","2003-05-26 00:00:00","","0.00","0.00"

The field in question appears empty, but at this point it has been selected, exported, opened in Notepad.

Regards,

Mark Spruill

-----Original Message-----
From: Tom Lane [mailto:tgl@sss.pgh.pa.us]
Sent: Wednesday, June 23, 2004 4:26 PM
To: Mark Spruill
Cc: pgsql-general@postgresql.org
Subject: Re: [GENERAL] Dump produces file with new line characters

"Mark Spruill" <mark.spruill@mightyautoparts.com> writes:

We are using Postgres 7.3 on Red Hat 9. We are doing dumps with a script that does:
pg_dump databasename > outfile 2>> logfile
The resulting dump files occasionally have a \N at the end of a line of data following the copy command. This causes a problem when I try to load them back in bacause psql thinks the \N (a new line character?) is a psql command. So, how do I avoid the \N in the dump and/or ignore it in the reload?

This is a new one on me. Can you show a specific example?

Also, 7.3.what exactly?

regards, tom lane

"Mark Spruill" <mark.spruill@mightyautoparts.com> writes:

Following is an excerpt from the dump file.

COPY compmstr (alienvendorcode, alienlinecode, alienpartnumber, jobber, list, da
te, replacedbypart, specialmarkets, discount) FROM stdin;
001 66 16-4002 32.50 65.65 2003-05-26 00:00:00
\N 0.00 0.00
001 66 16-4003 32.50 65.65 2003-05-26 00:00:00
\N 0.00 0.00
001 66 16-4006 32.50 65.65 2003-05-26 00:00:00
\N 0.00 0.00
001 66 16-4013 32.50 65.65 2003-05-26 00:00:00
\N 0.00 0.00

See what I mean? I am wondering if there is actually a new line character in the database or if the \N is representing a NULL value?

The \N's represent nulls, yes. The question is why psql has a problem
with them. It should know that it's inside COPY data and not
misinterpret them as psql commands. This is not something that's
changed lately --- we've always handled NULLs like this --- so I'm
mystified why you are having a problem. Can you characterize the cases
in which psql gets confused?

regards, tom lane

Tom,

I have solved the problem. I don't know exactly what I did, but I think it had something to do with a screwed up "template1". When I first tried to load the database, I connected to template1 instead of the database I wanted to load. Things went down hill from there. So I finally just re-initialized the whole database cluster and now it seems to be working OK. I guess this one was just stupid user error, but I learned a lesson. Don't mess with template1!

Thanks for your help,

Mark

-----Original Message-----
From: Tom Lane [mailto:tgl@sss.pgh.pa.us]
Sent: Wednesday, June 23, 2004 5:53 PM
To: Mark Spruill
Cc: pgsql-general@postgresql.org
Subject: Re: [GENERAL] Dump produces file with new line characters

"Mark Spruill" <mark.spruill@mightyautoparts.com> writes:

Following is an excerpt from the dump file.

COPY compmstr (alienvendorcode, alienlinecode, alienpartnumber, jobber, list, da
te, replacedbypart, specialmarkets, discount) FROM stdin;
001 66 16-4002 32.50 65.65 2003-05-26 00:00:00
\N 0.00 0.00
001 66 16-4003 32.50 65.65 2003-05-26 00:00:00
\N 0.00 0.00
001 66 16-4006 32.50 65.65 2003-05-26 00:00:00
\N 0.00 0.00
001 66 16-4013 32.50 65.65 2003-05-26 00:00:00
\N 0.00 0.00

See what I mean? I am wondering if there is actually a new line character in the database or if the \N is representing a NULL value?

The \N's represent nulls, yes. The question is why psql has a problem
with them. It should know that it's inside COPY data and not
misinterpret them as psql commands. This is not something that's
changed lately --- we've always handled NULLs like this --- so I'm
mystified why you are having a problem. Can you characterize the cases
in which psql gets confused?

regards, tom lane