Is 'changed' mandatory for a network object?

[Laurent Joncheray lpj@localhost]

	Hi everybody, i'd like to know if the 'changed' attribute
for the network object is mandatory. RIPE-50.txt does not say anything.
and the DB software configuration file says it's mandatory.
	Thanks,
		Laurent
 
-- 
Laurent Joncheray,                                 E-Mail: lpj@localhost
    Merit Network Inc, 1071 Beal Avenue,           Phone:  +1 (313) 936 2065
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