Re: pg_sample

On 08/27/2018 08:33 AM, Naveen Dabas wrote:
> actually i want limited data from the postgres database. But i don't
> want to use .csv

Does the sample need to include parent/child relationships?

In Postgres 9.5+ there is TABLESAMPLE:

https://www.postgresql.org/docs/10/static/sql-select.html

So you can do something like:

select * from plant1 TABLESAMPLE system (25);

on a single table.

I could see doing the above in a program and INSERTing the output to
another database.

>
>
>
> thanks
>
> On Mon, Aug 27, 2018 at 7:42 PM, Adrian Klaver
> <adrian(dot)klaver(at)aklaver(dot)com <mailto:adrian(dot)klaver(at)aklaver(dot)com>> wrote:
>
> On 08/26/2018 11:03 PM, Naveen Dabas wrote:
>
> Server encoding is UTF8
> Client encoding is UTF8
> Creating sample schema sampledb1
> DBD::Pg::db do failed: ERROR:  cannot execute CREATE SCHEMA in a
> read-only transaction at ./pg_sample line 296.
> main::__ANON__('DBD::Pg::db do failed: ERROR:  cannot execute
> CREATE SCHEMA i...', 'DBI::db=HASH(0xab2388)', undef) called at
> ./pg_sample line 478
> Done.
>
>
> can you help me in this
>
>
> Yes, by suggesting you try something other then pg_sample. The last
> commit was 4 years ago and it does not seem to be up to date enough.
>
> What sort of sampling do you want to do?
>
> thanks
>
>
> On Mon, Aug 27, 2018 at 11:16 AM, Naveen Dabas
> <naveen(at)paymonk(dot)com <mailto:naveen(at)paymonk(dot)com>
> <mailto:naveen(at)paymonk(dot)com <mailto:naveen(at)paymonk(dot)com>>> wrote:
>
>     Thanks for the help.
>     But now i'm getting some different error as i rum this command
>     ./pg_sample -a -f file.sql --limit="user = 100"
> --schema=dbname -h
>     hostname -U user -W password
>
>     I am not getting output and one file opens , in that file
> there id
>     guide for pg_sample
>     ----
>     /tmp/9REOT5C
>
>     NAME
>     pg_sample - extract a small, sample dataset from a larger
> PostgreSQL
>     database while maintaining referential integrity.
>     =head1 SYNOPSIS
>     pg_sample [ option... ] [ dbname ]
>     =head1 DESCRIPTION
>     pg_sample is a utility for exporting a small, sample
> dataset from a
>     larger PostgreSQL database. The output and command-line
> options closely
>     resemble the pg_dump backup utility (although only the
> plain-text format
>     is supported).
>     The sample database produced includes all tables from the
> original,
>     maintains referential integrity, and supports circular
> dependencies.
>     To build an actual instance of the sample database, the
> output of
>     this script
>     can be piped to the psql utility. For example, assuming we
> have an
>     existing
>     PostgreSQL database named "mydb", a sample database could be
>     constructed with:
>        createdb sampledb
>        pg_sample mydb | psql sampledb
>     and so on .......
>
>     On Mon, Aug 27, 2018 at 1:27 AM, Paul Carlucci
>     <paul(dot)carlucci(at)gmail(dot)com <mailto:paul(dot)carlucci(at)gmail(dot)com>
> <mailto:paul(dot)carlucci(at)gmail(dot)com
> <mailto:paul(dot)carlucci(at)gmail(dot)com>>> wrote:
>
>         sudo yum install perl-CPAN
>
>         Also do a "yum search perl-" and you should find most,
> if not
>         all what you need natively packaged for your particular
> Linux
>         distro.  You're better off just sticking with the
> pre-packaged
>         perl modules unless you specifically need something
> special.
>
>         You'll find more modules if you also enable the EPEL
> yum repo by
>         setting enabled=1 in the first section of
>         /etc/yum.repos.d/epel.conf and rerunning that yum
> search command.
>
>         On Sun, Aug 26, 2018, 2:20 PM Naveen Dabas
> <naveen(at)paymonk(dot)com <mailto:naveen(at)paymonk(dot)com>
>         <mailto:naveen(at)paymonk(dot)com
> <mailto:naveen(at)paymonk(dot)com>>> wrote:
>
>             Sir i'm getting error in both commands
>
>             [root(at)ip-88-8-8-17 ~]#  perl -MCPAN -e 'install
> Bundle::DBI'
>             Can't locate CPAN.pm in @INC (@INC contains:
>             /usr/local/lib64/perl5 /usr/local/share/perl5
>             /usr/lib64/perl5/vendor_perl
> /usr/share/perl5/vendor_perl
>             /usr/lib64/perl5 /usr/share/perl5 .).
>             BEGIN failed--compilation aborted.
>             [root(at)ip-88-8-8-17 ~]# perl -MCPAN -e 'install DBD::Pg'
>             Can't locate CPAN.pm in @INC (@INC contains:
>             /usr/local/lib64/perl5 /usr/local/share/perl5
>             /usr/lib64/perl5/vendor_perl
> /usr/share/perl5/vendor_perl
>             /usr/lib64/perl5 /usr/share/perl5 .).
>             BEGIN failed--compilation aborted.
>
>
>
>             operating system =CentOS Linux release 7.5.1804 (Core)
>
>             thanks
>
>
>             On Fri, Aug 24, 2018 at 6:16 PM, Abhinav Mehta
>             <abhinav(at)metarain(dot)com <mailto:abhinav(at)metarain(dot)com>
> <mailto:abhinav(at)metarain(dot)com <mailto:abhinav(at)metarain(dot)com>>> wrote:
>
>                 Solution, execute this on your linux terminal -
>
>                 $ perl -MCPAN -e 'install Bundle::DBI'
>                 $ perl -MCPAN -e 'install DBD::Pg'
>
>                  > On 24-Aug-2018, at 6:13 PM, Ravi Krishna
>                 <sravikrishna(at)aol(dot)com
> <mailto:sravikrishna(at)aol(dot)com> <mailto:sravikrishna(at)aol(dot)com
> <mailto:sravikrishna(at)aol(dot)com>>> wrote:
>                  >
>                  >>
>                  >> sir have taken pg_sample
>                  >> Now i want to run pg_sample with credential
> but i'm
>                 getting this error
>                  >>
>                  >> Can't locate DBI.pm in @INC (@INC contains:
>                 /usr/local/lib64/perl5 /usr/local/share/perl5
>                 /usr/lib64/perl5/vendor_perl
>                 /usr/share/perl5/vendor_perl /usr/lib64/perl5
>                 /usr/share/perl5 .) at ./pg_sample line 192.
>                  >> BEGIN failed--compilation aborted at
> ./pg_sample
>                 line 192.
>                  >
>                  > As is clear from the message, you need to
> install
>                 Perl DBI/DBD first.
>                  >
>                  >
>
>
>
>
>             --             --
>             With Regards
>             Naveen Dabas
>             Ph. 9017298370
>
>
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>
>
>
>     --     --
>     With Regards
>     Naveen Dabas
>     Ph. 9017298370
>
>
>
>
> --
> --
> With Regards
> Naveen Dabas
> Ph. 9017298370
>
>
> *Important Disclaimer:* Information contained in this email is
> for the recipient primarily addressed to. If you are not the
> primary recipient or are not supposed to receive this email, you
> are advised to kindly delete the email or the thread and notify
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> of *ACTAS TECHNOLOGIES PRIVATE LIMITED*. Do not use it without
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>
>
>
> --
> Adrian Klaver
> adrian(dot)klaver(at)aklaver(dot)com <mailto:adrian(dot)klaver(at)aklaver(dot)com>
>
>
>
>
> --
> --
> With Regards
> Naveen Dabas
> Ph. 9017298370
>
>
> *Important Disclaimer:* Information contained in this email is for the
> recipient primarily addressed to. If you are not the primary recipient
> or are not supposed to receive this email, you are advised to kindly
> delete the email or the thread and notify of the error. The logo is a
> registered and copyrighted property of *ACTAS TECHNOLOGIES PRIVATE
> LIMITED*. Do not use it without authorization.

--
Adrian Klaver
adrian(dot)klaver(at)aklaver(dot)com