On ΠαÏ? 31 Î?Ï?γ 2012 09:19:26 Chris Angelico wrote: > On Thu, Aug 30, 2012 at 4:42 PM, Achilleas Mantzios > <achill@xxxxxxxxxxxxxxxxxxx> wrote: > > I have found useful the use of variable assignment in psql, e.g. > > > > #!/bin/sh > > > > # lets say you have some var with a value, or even populate some var with a value from > > # psql as shown below > > somevar=`psql -P pager=off -q -t -c "SELECT foo from bar" | head -1 | sed -e 's/ //g'` > > > > # now use that variable in psql, (what you want to achieve), but in more tight manner > > # than simple shell substitution (see -v switch and : notation) > > > > psql -P pager=off -q -v somevar=$somevar -c "select foo2 from bar2 where var=:somevar" > > At this point, I have to ask: Why not switch to a language with actual > Postgres bindings? Try Python, or Pike, or something; I'm sure it's > going to be easier than doing everything through shell scripts. > or perl, or php, or java, etc... actually we "switched" to java some 11 years ago to build our infrastructure, but occasionally (or not so occasionally, but rather being part of the architecture) still sh/bach/tcsh/perl are heavily used and have their place. Its all about taste/preference and not easily jumping into overkill mode. OTOH the OP asked for doing exactly what -v (--set) var assignments are supposed to do. (lift shell substitution ambiguities about escaping and var expansion) > ChrisA > > > - Achilleas Mantzios IT DEPT -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
