Readline-style editing (arrow keys, word deletion, command history, etc.) is a feature that most users expect out of a command-line application on Linux. And one that is painfully missing from Oracle sqlplus (the equivalent to psql).

Of course, Debian has a solution:

apt-get install rlwrap
rlwrap sqlplus

You may also find it useful if, for some reason, you need to use the dash shell interactively.