[Pkg-grass-general] GRASS: how to learn the database language?

[Dan Jacobson <jidanni@jidanni.org>]

In GRASS I saw an example and was able to do it:
$ echo "select * from largeB" | db.select
What Debian package should I download to learn about this language?
At this point all I can do is grope in the dark:
$ echo "select 2 from largeB" | db.select #fails