sql query

I cannot figure out this sql query i'm needing. 

i have two tables..(table_1) below

timestamp        &nb sp;   ip2                             file2      & nbsp;         & nbsp;         & nbsp;         u sername2
1074979888 12.154.102.227 http://www.url.com                             admin

table_2:

id username email password key validated admin ip lastip file time file2

1    test        m@m   2342342    41         &nbs p; 1           ; 0     1.1 1.1    http:  21  http

the 1st table holds temporary data, it's login data that gets updated every 5 minutes.  i'm wanting to show the most current entry for each username in the 1st table based off of the most current timestamp.  in other words, if user "test" is logged in and table 1 has entries of him being at page2.htm page4.htm page5.htm, i want to select the most recent page he/she was at based off of the most recent timestamp in table_1 where table 1.username2 = table_2.username.

can someone fill me in on how to do this?