How to turn off header only in psql (postgresql)
When executing psql from shell you can use -t (prints tuples only) option:

$ psql -t -c "SELECT version();"
 PostgreSQL 9.5.5 on x86_64-pc-linux-gnu, compiled by gcc (Debian 4.9.2-10) 4.9.2, 64-bit


Within psql use \t to turn off printing header and row count.