Re: How can exe files such as 'pg_dump' be called from stored functions?

Steve, you're right! After permission was changed, the function works!

Thanks Tom, too! When I wrote my entry, although I had tried to debug
by outputting errors using '<', I used it to the same directory as the
output file, which prevented any message from appearing because of the
same permission issue.

This active mailinglist is very helpful for a novice as myself. Thanks a lot!

Sam

On Feb 7, 2008 6:29 PM, Steve Crawford <scrawford(at)pinpointresearch(dot)com> wrote:
>
> Tom Lane wrote:
>
> "Satoru Fukushima" <satoruf(at)gmail(dot)com> writes:
>
>
> can execute 'pg_dump', which produces an output file. However, when I
> made it as a stored function in C, it didn't work. Within the stored
> function, I used the exact same 'system' command. The other parts
> within the function such as getting input values, calculating, and
> returning outputs works and no error is produced. It looks that just
> the system("pg_dump"); command is passed without outputting anything.
>
> Are you making any effort at all to check for errors? It's not apparent
> from this code...
>
> The simplest approach to debugging this might be to dump stderr into
> some file, say
>
> system("pg_dump -f /path/to/output/file database_name 2>/tmp/pgdumperrs");
>
> and see what ends up in that file.
>
> Like, perhaps, the owner of the PostgreSQL server process having no
> permission to write into /path/to/output/file?
>
> Cheers,
> Steve
>