Postmodern (https://quickref.common-lisp.net/postmodern.htm https://quickref.common-lisp.net/postmodern.htm), a library to interface with Postresql will use the

Postmodern (https://quickref.common-lisp.net/postmodern.htm https://quickref.common-lisp.net/postmodern.htm), a library to interface with Postresql will use the keyword `:null` to represent null, and T and nil to represent boolean true and false.