Updating one worksheet using data from anothe

Hello,

Document name: csg_na_event_table_D-2010-09-03.xls
Tab/worksheet to be updated: csg_na_eventinfo
Tab/worksheet that has data that needs to be copied into csg_na_eventinfo: Sheet1

csg_na_eventinfo tab/worksheet looks like this:

event_id min_alarm_date max_alarm_date
XP123
XT08K
LT005

Sheet1 tab/worksheet looks like this:

event_id min_alarm_date max_alarm_date
XP123 2002-08-01 2008-03-07
OPL34 1998-01-13 2010-02-15
ACFIRE 2005-03-19 2005-03-19
XT08K 2001-08-13 2009-12-07
LT005 1995-06-26 2010-08-13

I want to be able to update the min_alarm_date and max_alarm_date columns in csg_na_eventinfo where csg_na_eventinfo.event_id = Sheet1.event_id.

Please help. Thank you.