Thread: pg_dump end comment
This might seem a bit silly, but is there any chance we could add a comment at the end of pg_dump text output that says '-- End of dump'? Would make it useful for checking that you actually have a complete dump... Chris
Christopher Kings-Lynne <chriskl@familyhealth.com.au> writes:
> This might seem a bit silly, but is there any chance we could add a
> comment at the end of pg_dump text output that says '-- End of dump'?
Sure --- while you're at it, put a "beginning of dump" at the start.
Is it worth adding the database name and/or other command-line
parameters given to pg_dump?
One thing to think about is the difference between a bare pg_dump and a
pg_dump/pg_restore sequence. Should these always generate identical
text output? (They do as of CVS tip, I believe, though this was not
always true before.)
Possibly this is all gilding the lily though...
regards, tom lane
Tom Lane wrote: > Christopher Kings-Lynne <chriskl@familyhealth.com.au> writes: > > This might seem a bit silly, but is there any chance we could add a > > comment at the end of pg_dump text output that says '-- End of dump'? > > Sure --- while you're at it, put a "beginning of dump" at the start. > > Is it worth adding the database name and/or other command-line > parameters given to pg_dump? > > One thing to think about is the difference between a bare pg_dump and a > pg_dump/pg_restore sequence. Should these always generate identical > text output? (They do as of CVS tip, I believe, though this was not > always true before.) > > Possibly this is all gilding the lily though... I like an end-of-dump marker for folks who want to check if the dump got truncated somehow. I can see how to do that for text dumps, but what about for tar or custom dumps? -- 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, Pennsylvania19073
On Tue, 30 Mar 2004, Bruce Momjian wrote: > Tom Lane wrote: > > Christopher Kings-Lynne <chriskl@familyhealth.com.au> writes: > > > This might seem a bit silly, but is there any chance we could add a > > > comment at the end of pg_dump text output that says '-- End of dump'? > > > > Sure --- while you're at it, put a "beginning of dump" at the start. > > > > Is it worth adding the database name and/or other command-line > > parameters given to pg_dump? > > > > One thing to think about is the difference between a bare pg_dump and a > > pg_dump/pg_restore sequence. Should these always generate identical > > text output? (They do as of CVS tip, I believe, though this was not > > always true before.) > > > > Possibly this is all gilding the lily though... > > I like an end-of-dump marker for folks who want to check if the dump got > truncated somehow. I can see how to do that for text dumps, but what > about for tar or custom dumps? Wouldn't it be more effective to test for non zero return status as this handles -Fc cases, etc, which would be non-trivial to test. Gavin
Gavin Sherry <swm@linuxworld.com.au> writes:
> On Tue, 30 Mar 2004, Bruce Momjian wrote:
>> I like an end-of-dump marker for folks who want to check if the dump got
>> truncated somehow. I can see how to do that for text dumps, but what
>> about for tar or custom dumps?
> Wouldn't it be more effective to test for non zero return status as this
> handles -Fc cases, etc, which would be non-trivial to test.
In the tar and custom archive formats, it's fairly obvious if the file
was truncated: you'll have table-of-contents entries that point past
the end of file. The only case that really needs an endmarker is
textual scripts --- both straight from pg_dump, and produced by
pg_restore.
regards, tom lane
Gavin Sherry wrote: > On Tue, 30 Mar 2004, Bruce Momjian wrote: > > > Tom Lane wrote: > > > Christopher Kings-Lynne <chriskl@familyhealth.com.au> writes: > > > > This might seem a bit silly, but is there any chance we could add a > > > > comment at the end of pg_dump text output that says '-- End of dump'? > > > > > > Sure --- while you're at it, put a "beginning of dump" at the start. > > > > > > Is it worth adding the database name and/or other command-line > > > parameters given to pg_dump? > > > > > > One thing to think about is the difference between a bare pg_dump and a > > > pg_dump/pg_restore sequence. Should these always generate identical > > > text output? (They do as of CVS tip, I believe, though this was not > > > always true before.) > > > > > > Possibly this is all gilding the lily though... > > > > I like an end-of-dump marker for folks who want to check if the dump got > > truncated somehow. I can see how to do that for text dumps, but what > > about for tar or custom dumps? > > Wouldn't it be more effective to test for non zero return status as this > handles -Fc cases, etc, which would be non-trivial to test. Yes, they have to check for a proper exit from pg_dump, but there is still a file sitting around after the dump, with no way to tell if it is accurate. -- 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, Pennsylvania19073
At 12:13 AM 31/03/2004, Bruce Momjian wrote:
>Yes, they have to check for a proper exit from pg_dump, but there is
>still a file sitting around after the dump, with no way to tell if it is
>accurate.
Why don't we write a hash into the header or footer. Then use something like:
pg_restore --verify <dump-file>
if file integrity is the objective.
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>>I like an end-of-dump marker for folks who want to check if the dump got >>truncated somehow. I can see how to do that for text dumps, but what >>about for tar or custom dumps? > > Wouldn't it be more effective to test for non zero return status as this > handles -Fc cases, etc, which would be non-trivial to test. That assumes you are there at the time of dump... Chris
On Wed, 31 Mar 2004, Philip Warner wrote: > At 12:13 AM 31/03/2004, Bruce Momjian wrote: > >Yes, they have to check for a proper exit from pg_dump, but there is > >still a file sitting around after the dump, with no way to tell if it is > >accurate. > > Why don't we write a hash into the header or footer. Then use something like: > > pg_restore --verify <dump-file> > > if file integrity is the objective. I like this idea. Nice to be able to check the md5 sig to make sure a backup is not corrupted OR short.