Time Stamp of a table????

Is there a way to determine (via time stamp) if a table has being updated
(/inserted/deleted). I used to use COMMENT statement following a updating so
that I can check LAST_DDL_TIME in table USER_OBJECTS. Unforturnately I have to find an alternative since DLLs are not supported in a trigger body. In an application, I have to inform all clients (when they login) that a new copy
(update/insert/delete) of table is available. How can I do it??

Thanks

Jizhong
jizwang_at_cc.umanitoba.ca

Jizhong Wang, Ph.D.                   		jizwang_at_cc.umanitoba.ca
Systems Analyst, Information Services
St. Boniface General Hospital			Tel. 204-235-3326
Winnipeg, Canada				Fax. 204-237-6229
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