Thread: Re: [HACKERS] pg_dump --comment?
Jon Jensen wrote:
> On Fri, 28 May 2004, Christopher Kings-Lynne wrote:
>
> > > I've encountered a situation where I'd like to store some information
> > > about the database when I do a pg_dump. For instance, the timestamp of
> > > the dump. And some other information that I pull from the database.
> >
> > I think every dump should dump the timestamp regardless...
>
> That would cause me a lot of trouble. Every night I do a pg_dump on all my
> databases to a temporary file. Then I use cmp to compare that dump to last
> night's dump. If they're identical I just delete the new dump so that only
> the old one remains, with its original timestamp. That way rsync doesn't
> see any change, and doesn't waste any time comparing it when we do
> backups. It's also handy to see the last day the dump changed by looking
> at the file's timestamp.
>
> Granted, this is only of interest on databases that don't change at all,
> but on a multi-user system we have a surprising number of databases that
> don't change at all for days (alongside the ones that change all the time,
> of course).
>
> However, I would like to see an option to include the timestamp if someone
> wants it.
The following patch adds start/stop times for pg_dump and pg_dumpall
when verbose output is selected:
--
-- PostgreSQL database cluster dump
-- Started on 2004-06-04 01:01:35 EDT
--
--
-- PostgreSQL database dump
-- Started on 2004-06-04 01:01:36 EDT
--
--
-- PostgreSQL database dump complete
-- Completed on 2004-06-04 01:01:36 EDT
--
--
-- PostgreSQL database cluster dump complete
-- Completed on 2004-06-04 01:01:36 EDT
--
--
Bruce Momjian | http://candle.pha.pa.us
pgman@candle.pha.pa.us | (610) 359-1001
+ If your life is a hard drive, | 13 Roberts Road
+ Christ can be your backup. | Newtown Square, Pennsylvania 19073
Index: doc/src/sgml/ref/pg_dump.sgml
===================================================================
RCS file: /cvsroot/pgsql-server/doc/src/sgml/ref/pg_dump.sgml,v
retrieving revision 1.70
diff -c -c -r1.70 pg_dump.sgml
*** doc/src/sgml/ref/pg_dump.sgml 31 May 2004 13:37:52 -0000 1.70
--- doc/src/sgml/ref/pg_dump.sgml 4 Jun 2004 04:58:18 -0000
***************
*** 403,409 ****
<para>
Specifies verbose mode. This will cause
<application>pg_dump</application> to output detailed object
! comments in the dump file, and progress messages to standard error.
</para>
</listitem>
</varlistentry>
--- 403,410 ----
<para>
Specifies verbose mode. This will cause
<application>pg_dump</application> to output detailed object
! comments in the dump file, start and stop times, and progress
! messages to standard error.
</para>
</listitem>
</varlistentry>
Index: doc/src/sgml/ref/pg_dumpall.sgml
===================================================================
RCS file: /cvsroot/pgsql-server/doc/src/sgml/ref/pg_dumpall.sgml,v
retrieving revision 1.43
diff -c -c -r1.43 pg_dumpall.sgml
*** doc/src/sgml/ref/pg_dumpall.sgml 29 Nov 2003 19:51:39 -0000 1.43
--- doc/src/sgml/ref/pg_dumpall.sgml 4 Jun 2004 04:58:18 -0000
***************
*** 192,199 ****
<listitem>
<para>
Specifies verbose mode. This will cause
! <application>pg_dumpall</application> to print progress
! messages to standard error.
</para>
</listitem>
</varlistentry>
--- 192,200 ----
<listitem>
<para>
Specifies verbose mode. This will cause
! <application>pg_dumpall</application> to output start and stop
! times in the dump file, and progress messages to standard error.
! It will also enable verbose output in <application>pg_dump</>.
</para>
</listitem>
</varlistentry>
Index: src/bin/pg_dump/pg_backup_archiver.c
===================================================================
RCS file: /cvsroot/pgsql-server/src/bin/pg_dump/pg_backup_archiver.c,v
retrieving revision 1.87
diff -c -c -r1.87 pg_backup_archiver.c
*** src/bin/pg_dump/pg_backup_archiver.c 19 May 2004 21:21:26 -0000 1.87
--- src/bin/pg_dump/pg_backup_archiver.c 4 Jun 2004 04:58:21 -0000
***************
*** 28,33 ****
--- 28,34 ----
#include <ctype.h>
#include <errno.h>
+ #include <time.h>
#include <unistd.h>
#include "pqexpbuffer.h"
***************
*** 202,208 ****
if (ropt->filename || ropt->compression)
sav = SetOutput(AH, ropt->filename, ropt->compression);
! ahprintf(AH, "--\n-- PostgreSQL database dump\n--\n\n");
/*
* Establish important parameter values right away.
--- 203,218 ----
if (ropt->filename || ropt->compression)
sav = SetOutput(AH, ropt->filename, ropt->compression);
! ahprintf(AH, "--\n-- PostgreSQL database dump\n");
! if (AH->public.verbose)
! {
! char buf[256];
! time_t now = time(NULL);
!
! if (strftime(buf, 256, "%Y-%m-%d %H:%M:%S %Z", localtime(&now)) != 0)
! ahprintf(AH, "-- Started on %s\n", buf);
! }
! ahprintf(AH, "--\n\n");
/*
* Establish important parameter values right away.
***************
*** 385,391 ****
}
}
! ahprintf(AH, "--\n-- PostgreSQL database dump complete\n--\n\n");
}
/*
--- 395,410 ----
}
}
! ahprintf(AH, "--\n-- PostgreSQL database dump complete\n");
! if (AH->public.verbose)
! {
! char buf[256];
! time_t now = time(NULL);
!
! if (strftime(buf, 256, "%Y-%m-%d %H:%M:%S %Z", localtime(&now)) != 0)
! ahprintf(AH, "-- Completed on %s\n", buf);
! }
! ahprintf(AH, "--\n\n");
}
/*
Index: src/bin/pg_dump/pg_dumpall.c
===================================================================
RCS file: /cvsroot/pgsql-server/src/bin/pg_dump/pg_dumpall.c,v
retrieving revision 1.36
diff -c -c -r1.36 pg_dumpall.c
*** src/bin/pg_dump/pg_dumpall.c 3 Jun 2004 00:07:36 -0000 1.36
--- src/bin/pg_dump/pg_dumpall.c 4 Jun 2004 04:58:22 -0000
***************
*** 21,26 ****
--- 21,27 ----
#include "strdup.h"
#endif
#include <errno.h>
+ #include <time.h>
#include "getopt_long.h"
***************
*** 219,226 ****
conn = connectDatabase("template1", pghost, pgport, pguser, force_password);
! printf("--\n");
! printf("-- PostgreSQL database cluster dump\n");
printf("--\n\n");
printf("\\connect \"template1\"\n\n");
--- 220,234 ----
conn = connectDatabase("template1", pghost, pgport, pguser, force_password);
! printf("--\n-- PostgreSQL database cluster dump\n");
! if (verbose)
! {
! char buf[256];
! time_t now = time(NULL);
!
! if (strftime(buf, 256, "%Y-%m-%d %H:%M:%S %Z", localtime(&now)) != 0)
! printf("-- Started on %s\n", buf);
! }
printf("--\n\n");
printf("\\connect \"template1\"\n\n");
***************
*** 239,246 ****
PQfinish(conn);
! printf("--\n");
! printf("-- PostgreSQL database cluster dump complete\n");
printf("--\n\n");
exit(0);
--- 247,261 ----
PQfinish(conn);
! printf("--\n-- PostgreSQL database cluster dump complete\n");
! if (verbose)
! {
! char buf[256];
! time_t now = time(NULL);
!
! if (strftime(buf, 256, "%Y-%m-%d %H:%M:%S %Z", localtime(&now)) != 0)
! printf("-- Completed on %s\n", buf);
! }
printf("--\n\n");
exit(0);
Bruce Momjian <pgman@candle.pha.pa.us> writes:
> The following patch adds start/stop times for pg_dump and pg_dumpall
What happens in a pg_dump -Fc / pg_restore scenario?
regards, tom lane
Tom Lane wrote: > Bruce Momjian <pgman@candle.pha.pa.us> writes: > > The following patch adds start/stop times for pg_dump and pg_dumpall > > What happens in a pg_dump -Fc / pg_restore scenario? Uh, do those markers not appear in that dump type? I thought they did. I just tried pg_restore -v and while I see the lines, they are changing every time I run it, meaning it isn't stored in the file but is showing current time. I looked in the dump file and I don't see the dates either. So, in non-ascii format, I need to dump a comment record and read it back on restore? Yuck. Anyone want to tackle that? -- Bruce Momjian | http://candle.pha.pa.us pgman@candle.pha.pa.us | (610) 359-1001 + If your life is a hard drive, | 13 Roberts Road + Christ can be your backup. | Newtown Square, Pennsylvania 19073
Bruce Momjian <pgman@candle.pha.pa.us> writes:
> Tom Lane wrote:
>> What happens in a pg_dump -Fc / pg_restore scenario?
> So, in non-ascii format, I need to dump a comment record and read it
> back on restore? Yuck. Anyone want to tackle that?
Yes. Hacking the output routines alone is almost never the right way
to do things in pg_dump.
My feeling is that if anyone cares to tackle this, it would be
appropriate to add a record type that carries a user-supplied
comment, and then people could do something like
pg_dump --comment "generated on `date`"
if they want to have a timestamp. I don't want a timestamp put
into the file by default, because that creates problems for
comparing dump files.
regards, tom lane
Tom Lane wrote:
> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> > Tom Lane wrote:
> >> What happens in a pg_dump -Fc / pg_restore scenario?
>
> > So, in non-ascii format, I need to dump a comment record and read it
> > back on restore? Yuck. Anyone want to tackle that?
>
> Yes. Hacking the output routines alone is almost never the right way
> to do things in pg_dump.
>
> My feeling is that if anyone cares to tackle this, it would be
> appropriate to add a record type that carries a user-supplied
> comment, and then people could do something like
> pg_dump --comment "generated on `date`"
> if they want to have a timestamp. I don't want a timestamp put
> into the file by default, because that creates problems for
> comparing dump files.
OK, new patch. This puts start/stop times into dumps if you use -v
during dumping. It creates a new node type:
--
-- PostgreSQL database dump
--
SET client_encoding = 'SQL_ASCII';
SET check_function_bodies = false;
--
-- Name: DUMP TIMESTAMP; Type: DUMP TIMESTAMP; Schema: -; Owner:
--
-- Started on 2004-06-05 00:41:25 EDT
...
--
-- Name: DUMP TIMESTAMP; Type: DUMP TIMESTAMP; Schema: -; Owner:
--
-- Completed on 2004-06-05 00:44:28 EDT
--
-- PostgreSQL database dump complete
--
One issue is that the system dumps certain settings into the output file
in ascii dumps, but pg_restore sets them on its own during the restore.
Because the timestamp can't be done during pg_restore, it has to be a
special node.
--
Bruce Momjian | http://candle.pha.pa.us
pgman@candle.pha.pa.us | (610) 359-1001
+ If your life is a hard drive, | 13 Roberts Road
+ Christ can be your backup. | Newtown Square, Pennsylvania 19073
Index: doc/src/sgml/ref/pg_dump.sgml
===================================================================
RCS file: /cvsroot/pgsql-server/doc/src/sgml/ref/pg_dump.sgml,v
retrieving revision 1.70
diff -c -c -r1.70 pg_dump.sgml
*** doc/src/sgml/ref/pg_dump.sgml 31 May 2004 13:37:52 -0000 1.70
--- doc/src/sgml/ref/pg_dump.sgml 5 Jun 2004 04:22:15 -0000
***************
*** 403,409 ****
<para>
Specifies verbose mode. This will cause
<application>pg_dump</application> to output detailed object
! comments in the dump file, and progress messages to standard error.
</para>
</listitem>
</varlistentry>
--- 403,410 ----
<para>
Specifies verbose mode. This will cause
<application>pg_dump</application> to output detailed object
! comments in the dump file, start and stop times, and progress
! messages to standard error.
</para>
</listitem>
</varlistentry>
Index: doc/src/sgml/ref/pg_dumpall.sgml
===================================================================
RCS file: /cvsroot/pgsql-server/doc/src/sgml/ref/pg_dumpall.sgml,v
retrieving revision 1.43
diff -c -c -r1.43 pg_dumpall.sgml
*** doc/src/sgml/ref/pg_dumpall.sgml 29 Nov 2003 19:51:39 -0000 1.43
--- doc/src/sgml/ref/pg_dumpall.sgml 5 Jun 2004 04:22:15 -0000
***************
*** 192,199 ****
<listitem>
<para>
Specifies verbose mode. This will cause
! <application>pg_dumpall</application> to print progress
! messages to standard error.
</para>
</listitem>
</varlistentry>
--- 192,200 ----
<listitem>
<para>
Specifies verbose mode. This will cause
! <application>pg_dumpall</application> to output start and stop
! times in the dump file, and progress messages to standard error.
! It will also enable verbose output in <application>pg_dump</>.
</para>
</listitem>
</varlistentry>
Index: src/bin/pg_dump/pg_dump.c
===================================================================
RCS file: /cvsroot/pgsql-server/src/bin/pg_dump/pg_dump.c,v
retrieving revision 1.373
diff -c -c -r1.373 pg_dump.c
*** src/bin/pg_dump/pg_dump.c 3 Jun 2004 00:07:36 -0000 1.373
--- src/bin/pg_dump/pg_dump.c 5 Jun 2004 04:22:21 -0000
***************
*** 32,37 ****
--- 32,38 ----
#ifdef HAVE_TERMIOS_H
#include <termios.h>
#endif
+ #include <time.h>
#ifndef HAVE_STRDUP
#include "strdup.h"
***************
*** 163,168 ****
--- 164,170 ----
static const char *fmtQualifiedId(const char *schema, const char *id);
static int dumpBlobs(Archive *AH, void *arg);
static void dumpDatabase(Archive *AH);
+ static void dumpTimestamp(Archive *AH, char *msg);
static void dumpEncoding(Archive *AH);
static const char *getAttrName(int attrnum, TableInfo *tblInfo);
static const char *fmtCopyColumnList(const TableInfo *ti);
***************
*** 598,603 ****
--- 600,608 ----
* in a safe order.
*/
+ if (g_fout->verbose)
+ dumpTimestamp(g_fout, "Started on");
+
/* First the special encoding entry. */
dumpEncoding(g_fout);
***************
*** 615,620 ****
--- 620,628 ----
dumpDumpableObject(g_fout, dobjs[i]);
}
+ if (g_fout->verbose)
+ dumpTimestamp(g_fout, "Completed on");
+
/*
* And finally we can do the actual output.
*/
***************
*** 1280,1285 ****
--- 1288,1322 ----
destroyPQExpBuffer(dbQry);
destroyPQExpBuffer(delQry);
destroyPQExpBuffer(creaQry);
+ }
+
+
+ /*
+ * dumpTimestamp
+ */
+ static void
+ dumpTimestamp(Archive *AH, char *msg)
+ {
+ char buf[256];
+ time_t now = time(NULL);
+
+ if (strftime(buf, 256, "%Y-%m-%d %H:%M:%S %Z", localtime(&now)) != 0)
+ {
+ PQExpBuffer qry = createPQExpBuffer();
+
+ appendPQExpBuffer(qry, "-- ");
+ appendPQExpBuffer(qry, msg);
+ appendPQExpBuffer(qry, " ");
+ appendPQExpBuffer(qry, buf);
+ appendPQExpBuffer(qry, "\n");
+
+ ArchiveEntry(AH, nilCatalogId, createDumpId(),
+ "DUMP TIMESTAMP", NULL, "",
+ false, "DUMP TIMESTAMP", qry->data, "", NULL,
+ NULL, 0,
+ NULL, NULL);
+ destroyPQExpBuffer(qry);
+ }
}