Equivalency of TOP predicate?

[Big Mike]

What  would be the equivalent of MS's TOP predicate in mySQL? I'm coming
from a Windows background and am only familiar, so far, with the SQL found
in the Jet engine (VB5 version). I'm moving from NT-based to UNIX-based web
apps.

example: "SELECT TOP 5 PERCENT * FROM table ORDER BY id DESC"

Are there any resources on the net that describe differences like this and
their equivalents?

Mike