Re: pg_dump fundenental question

Hello Adrian,

appreciate the prompt reply, thank you.

As stated in the original email, I want to know whether compression (whatever level) is on by default (or not) -  if I supply NO extra switches/options.
I have read the documentation and it is unclear in this respect. I am a Mainframer and perhaps have a different world view on how to explain things...

TIA and regards,


Henk.



On 07/05/2016 07:54 AM, J. Cassidy wrote:
> Hello all,
>
> I have hopefully an "easy" question.
>
> If I issue the pg_dump command with no switches or options i.e.
>
> /usr/local/pgsql/bin/pg_dump -v dbabcd > /data3TB/Backup/dbabcd
>
> Is their any "default" compression involved or not? Does pg_dump talk to
> zlib during the dump process given that I have not specified any
> compression on the
> command line? (see above).
>
> Your considered opinions would be much appreciated.

https://www.postgresql.org/docs/9.5/static/app-pgdump.html

"
-F format
--format=format

Selects the format of the output. format can be one of the following:

p
plain

Output a plain-text SQL script file (the default).
"

......

In line tag:

"-Z 0..9
--compress=0..9

Specify the compression level to use. Zero means no compression.
For the custom archive format, this specifies compression of individual
table-data segments, and the default is to compress at a moderate level.
<* SEE HERE For plain text output, setting a nonzero compression level
causes the entire output file to be compressed, as though it had been
fed through gzip; but the default is not to compress. SEE HERE *> The
tar archive format currently does not support compression at all.
"


>
>
> Regards,
>
>
> Henk
>


--
Adrian Klaver
adrian.klaver@aklaver.com



J