Run SQL from Vim

When I run <Leader>r from a .sql file in Vim, the file's contents are run against my Postgres database through psql and the output is printed to my screen.

The configuration for this is in ~/.vim/ftplugin/sql.vim:

" Run current file
nmap <buffer> <Leader>r :!clear && psql -d $(cat .db) -f %<CR>

I also have a .db file that contains only the local database name:

example_development

See man psql for more detail on the -d and -f flags.