I like having current time in my command prompts. It helps me keep track of how long a command has been running after I have become a little scared of losing all the progress the command has already made. It also allows for some cheap profiling.

To be able to do it in R, I created a small extension and doing it in bash is easy.

It is somewhat easier than R but trickier than bash to do in the psql. It is possible because you can actually embed output of shell commands while expanding the PROMPT1 variable! Since date is available on most systems, you can just execute it and embed the output of date into the prompt:

\set PROMPT1 '%`date +%H:%M:%S` >'

Personally, I like to have a dash of color on my prompts. Hence, I have the following line in my ~/.psqlrc file:

\set PROMPT1 '(%n@%M:%>) %[%033[00;33m%]%`date +%H:%M:%S`%[%033[00m%] [%[%033[01;31m%]%/%[%[%033[00m%]] > '