Php grab info from a database help

[The_Rs_Monkey]

once im connected to database, say $db, how would i get info from it from a username?

like i have a table with the following columns : username, password, online, onlinetime, totaltime
how would i get onlinetime, online,totaltime, by the appropiate username.
table is named siginfo

[rincewind456]

SELECT onlinetime, online, totaltime 
FROM siginfo
WHERE username='usernamehere'

[The_Rs_Monkey]

tyvm