[SYMBOL] [A] [B] [C] [D] [E] [F] [G] [H] [I] [J] [K] [L] [M] [N] [O] [P] [Q] [R] [S] [T] [U] [V] [W] [X] [Z] qed program, regular expressions and  queries, generic  [See PDBA::GQ] question mark (?), Perl regex metacharacter  2nd  question mark-question mark (??), Perl regex metacharacter  quotas, setting while creating user accounts  quote method (Perl DBI)