Using SQL to refer as Squirrel may just cause confusion among users.
And furthermore, those who aren't confused by it just take it as a sign of incompetence, the same way some people laugh at those who call Pawn "Pawno." (If you're wondering, Pawno is the
editor, Pawn is the
language.)
To answer the original post, this is a function that only exists in Squirrel
or must be manually set by an admin via RCON. mIRC also allows you to place markers, but mIRC is dead.