Hi Adrian: On Wed, Mar 4, 2015 at 1:03 AM, Adrian Klaver <adrian.kla...@aklaver.com> wrote:
> > As you pointed, my bet is in the -f case COPY FROM STDIN expects the >> data on the file ( otherwise pg_dumps would not work ), but your >> sugestion seems to have a problem of double redirection, let me elaborate: >> > > Well according to here, they should be roughly equivalent: > > http://www.postgresql.org/docs/9.3/interactive/app-psql.html > .... Yeah, they should, I' was not discussing you. I was pointing the SHELL line was incorrect, > Trying it showed they where and ended with the same result, the data was > not copied over:( > Of course, I'll be greatly surprissed if they did. > > > If I did this: > > psql -h host1 -U user1 -d db1 -f /q1.sql | psql -h host2 -U user2 -d db2 > -f - > > I saw the stdout from my 'q1.sql' show up at the second command, where it > threw an error because it was just the data without the COPY .. FROM > statement. So the second command must eat the stdin before it actually runs > q2.sql. Figured this would have been an easy fix. In my case for this sort > of thing I use Python/psycopg2 and its COPY TO/FROM commands and run it > through a buffer. Though of late I have starting using Pandas also. > Of course you end up with an error, I would have reported a bug otherwise. And also you are not using q2.sql so the result would have been wrong. I did send you a form ( what you've nicely quoted back ) : >> (cat q2.sql; psql -h host1 -U user1 -d db1 -f /q1.sql) | psql -h host2 >> -U user2 -d db2 >> > of putting q2.sql in front of the output from q1.sql in the same pipe, even with some samples of how this pipes works. Maybe you stopped reading too soon. I cannot try it as I do not have q1.sql or q2.sql, but given what I know about the reading/writing code of psql ( and that I have made this kinds of things before ) it should work. It's a classical shell construct, use a sub-shell ( parentheses ) to combine several commands and pipe its output to another one. The problem what all the others constructs seem to be trying to do it with a pipe of single commands, which is much more difficult. Of course, if the problemis due to inadequate shells ( as, say, cmd.exe ) it may need to be done in other ways. Regards. Francisco Olarte.
